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/* -*- mode: C++; indent-tabs-mode: nil; -*-
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 *
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 * This file is a part of LEMON, a generic C++ optimization library.
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 *
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 * Copyright (C) 2003-2009
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 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
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 * (Egervary Research Group on Combinatorial Optimization, EGRES).
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 *
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 * Permission to use, modify and distribute this software is granted
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 * provided that this copyright notice appears in all copies. For
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 * precise terms see the accompanying LICENSE file.
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 *
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 * This software is provided "AS IS" with no warranty of any kind,
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 * express or implied, and with no claim as to its suitability for any
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 * purpose.
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 *
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 */
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namespace lemon {
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/**
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@defgroup datas Data Structures
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This group contains the several data structures implemented in LEMON.
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*/
25 25

	
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/**
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@defgroup graphs Graph Structures
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@ingroup datas
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\brief Graph structures implemented in LEMON.
30 30

	
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The implementation of combinatorial algorithms heavily relies on
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efficient graph implementations. LEMON offers data structures which are
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planned to be easily used in an experimental phase of implementation studies,
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and thereafter the program code can be made efficient by small modifications.
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The most efficient implementation of diverse applications require the
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usage of different physical graph implementations. These differences
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appear in the size of graph we require to handle, memory or time usage
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limitations or in the set of operations through which the graph can be
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accessed.  LEMON provides several physical graph structures to meet
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the diverging requirements of the possible users.  In order to save on
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running time or on memory usage, some structures may fail to provide
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some graph features like arc/edge or node deletion.
44 44

	
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Alteration of standard containers need a very limited number of
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operations, these together satisfy the everyday requirements.
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In the case of graph structures, different operations are needed which do
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not alter the physical graph, but gives another view. If some nodes or
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arcs have to be hidden or the reverse oriented graph have to be used, then
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this is the case. It also may happen that in a flow implementation
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the residual graph can be accessed by another algorithm, or a node-set
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is to be shrunk for another algorithm.
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LEMON also provides a variety of graphs for these requirements called
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\ref graph_adaptors "graph adaptors". Adaptors cannot be used alone but only
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in conjunction with other graph representations.
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You are free to use the graph structure that fit your requirements
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the best, most graph algorithms and auxiliary data structures can be used
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with any graph structure.
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<b>See also:</b> \ref graph_concepts "Graph Structure Concepts".
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*/
63 63

	
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/**
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@defgroup graph_adaptors Adaptor Classes for Graphs
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@ingroup graphs
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\brief Adaptor classes for digraphs and graphs
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69 69
This group contains several useful adaptor classes for digraphs and graphs.
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The main parts of LEMON are the different graph structures, generic
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graph algorithms, graph concepts, which couple them, and graph
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adaptors. While the previous notions are more or less clear, the
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latter one needs further explanation. Graph adaptors are graph classes
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which serve for considering graph structures in different ways.
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A short example makes this much clearer.  Suppose that we have an
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instance \c g of a directed graph type, say ListDigraph and an algorithm
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\code
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template <typename Digraph>
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int algorithm(const Digraph&);
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\endcode
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is needed to run on the reverse oriented graph.  It may be expensive
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(in time or in memory usage) to copy \c g with the reversed
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arcs.  In this case, an adaptor class is used, which (according
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to LEMON \ref concepts::Digraph "digraph concepts") works as a digraph.
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The adaptor uses the original digraph structure and digraph operations when
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methods of the reversed oriented graph are called.  This means that the adaptor
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have minor memory usage, and do not perform sophisticated algorithmic
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actions.  The purpose of it is to give a tool for the cases when a
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graph have to be used in a specific alteration.  If this alteration is
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obtained by a usual construction like filtering the node or the arc set or
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considering a new orientation, then an adaptor is worthwhile to use.
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To come back to the reverse oriented graph, in this situation
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\code
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template<typename Digraph> class ReverseDigraph;
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\endcode
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template class can be used. The code looks as follows
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\code
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ListDigraph g;
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ReverseDigraph<ListDigraph> rg(g);
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int result = algorithm(rg);
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\endcode
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During running the algorithm, the original digraph \c g is untouched.
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This techniques give rise to an elegant code, and based on stable
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graph adaptors, complex algorithms can be implemented easily.
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In flow, circulation and matching problems, the residual
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graph is of particular importance. Combining an adaptor implementing
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this with shortest path algorithms or minimum mean cycle algorithms,
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a range of weighted and cardinality optimization algorithms can be
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obtained. For other examples, the interested user is referred to the
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detailed documentation of particular adaptors.
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The behavior of graph adaptors can be very different. Some of them keep
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capabilities of the original graph while in other cases this would be
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meaningless. This means that the concepts that they meet depend
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on the graph adaptor, and the wrapped graph.
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For example, if an arc of a reversed digraph is deleted, this is carried
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out by deleting the corresponding arc of the original digraph, thus the
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adaptor modifies the original digraph.
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However in case of a residual digraph, this operation has no sense.
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Let us stand one more example here to simplify your work.
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ReverseDigraph has constructor
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\code
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ReverseDigraph(Digraph& digraph);
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\endcode
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This means that in a situation, when a <tt>const %ListDigraph&</tt>
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reference to a graph is given, then it have to be instantiated with
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<tt>Digraph=const %ListDigraph</tt>.
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\code
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int algorithm1(const ListDigraph& g) {
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  ReverseDigraph<const ListDigraph> rg(g);
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  return algorithm2(rg);
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}
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\endcode
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*/
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/**
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@defgroup maps Maps
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@ingroup datas
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\brief Map structures implemented in LEMON.
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This group contains the map structures implemented in LEMON.
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LEMON provides several special purpose maps and map adaptors that e.g. combine
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new maps from existing ones.
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<b>See also:</b> \ref map_concepts "Map Concepts".
151 151
*/
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/**
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@defgroup graph_maps Graph Maps
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@ingroup maps
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\brief Special graph-related maps.
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This group contains maps that are specifically designed to assign
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values to the nodes and arcs/edges of graphs.
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If you are looking for the standard graph maps (\c NodeMap, \c ArcMap,
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\c EdgeMap), see the \ref graph_concepts "Graph Structure Concepts".
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*/
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/**
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\defgroup map_adaptors Map Adaptors
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\ingroup maps
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\brief Tools to create new maps from existing ones
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This group contains map adaptors that are used to create "implicit"
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maps from other maps.
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Most of them are \ref concepts::ReadMap "read-only maps".
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They can make arithmetic and logical operations between one or two maps
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(negation, shifting, addition, multiplication, logical 'and', 'or',
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'not' etc.) or e.g. convert a map to another one of different Value type.
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178 178
The typical usage of this classes is passing implicit maps to
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algorithms.  If a function type algorithm is called then the function
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type map adaptors can be used comfortable. For example let's see the
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usage of map adaptors with the \c graphToEps() function.
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\code
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  Color nodeColor(int deg) {
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    if (deg >= 2) {
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      return Color(0.5, 0.0, 0.5);
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    } else if (deg == 1) {
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      return Color(1.0, 0.5, 1.0);
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    } else {
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      return Color(0.0, 0.0, 0.0);
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    }
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  }
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  Digraph::NodeMap<int> degree_map(graph);
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  graphToEps(graph, "graph.eps")
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    .coords(coords).scaleToA4().undirected()
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    .nodeColors(composeMap(functorToMap(nodeColor), degree_map))
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    .run();
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\endcode
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The \c functorToMap() function makes an \c int to \c Color map from the
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\c nodeColor() function. The \c composeMap() compose the \c degree_map
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and the previously created map. The composed map is a proper function to
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get the color of each node.
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The usage with class type algorithms is little bit harder. In this
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case the function type map adaptors can not be used, because the
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function map adaptors give back temporary objects.
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\code
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  Digraph graph;
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  typedef Digraph::ArcMap<double> DoubleArcMap;
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  DoubleArcMap length(graph);
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  DoubleArcMap speed(graph);
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  typedef DivMap<DoubleArcMap, DoubleArcMap> TimeMap;
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  TimeMap time(length, speed);
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  Dijkstra<Digraph, TimeMap> dijkstra(graph, time);
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  dijkstra.run(source, target);
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\endcode
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We have a length map and a maximum speed map on the arcs of a digraph.
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The minimum time to pass the arc can be calculated as the division of
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the two maps which can be done implicitly with the \c DivMap template
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class. We use the implicit minimum time map as the length map of the
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\c Dijkstra algorithm.
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*/
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/**
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@defgroup paths Path Structures
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@ingroup datas
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\brief %Path structures implemented in LEMON.
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This group contains the path structures implemented in LEMON.
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LEMON provides flexible data structures to work with paths.
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All of them have similar interfaces and they can be copied easily with
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assignment operators and copy constructors. This makes it easy and
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efficient to have e.g. the Dijkstra algorithm to store its result in
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any kind of path structure.
240 240

	
241 241
\sa \ref concepts::Path "Path concept"
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*/
243 243

	
244 244
/**
245 245
@defgroup heaps Heap Structures
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@ingroup datas
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\brief %Heap structures implemented in LEMON.
248 248

	
249 249
This group contains the heap structures implemented in LEMON.
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LEMON provides several heap classes. They are efficient implementations
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of the abstract data type \e priority \e queue. They store items with
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specified values called \e priorities in such a way that finding and
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removing the item with minimum priority are efficient.
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The basic operations are adding and erasing items, changing the priority
256 256
of an item, etc.
257 257

	
258 258
Heaps are crucial in several algorithms, such as Dijkstra and Prim.
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The heap implementations have the same interface, thus any of them can be
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used easily in such algorithms.
261 261

	
262 262
\sa \ref concepts::Heap "Heap concept"
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*/
264 264

	
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/**
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@defgroup matrices Matrices
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@ingroup datas
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\brief Two dimensional data storages implemented in LEMON.
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270 270
This group contains two dimensional data storages implemented in LEMON.
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*/
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/**
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@defgroup auxdat Auxiliary Data Structures
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@ingroup datas
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\brief Auxiliary data structures implemented in LEMON.
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278 278
This group contains some data structures implemented in LEMON in
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order to make it easier to implement combinatorial algorithms.
280 280
*/
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282 282
/**
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@defgroup geomdat Geometric Data Structures
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@ingroup auxdat
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\brief Geometric data structures implemented in LEMON.
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This group contains geometric data structures implemented in LEMON.
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 - \ref lemon::dim2::Point "dim2::Point" implements a two dimensional
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   vector with the usual operations.
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 - \ref lemon::dim2::Box "dim2::Box" can be used to determine the
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   rectangular bounding box of a set of \ref lemon::dim2::Point
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   "dim2::Point"'s.
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*/
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/**
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@defgroup matrices Matrices
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@ingroup auxdat
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\brief Two dimensional data storages implemented in LEMON.
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This group contains two dimensional data storages implemented in LEMON.
302
*/
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/**
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@defgroup algs Algorithms
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\brief This group contains the several algorithms
285 307
implemented in LEMON.
286 308

	
287 309
This group contains the several algorithms
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implemented in LEMON.
289 311
*/
290 312

	
291 313
/**
292 314
@defgroup search Graph Search
293 315
@ingroup algs
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\brief Common graph search algorithms.
295 317

	
296 318
This group contains the common graph search algorithms, namely
297 319
\e breadth-first \e search (BFS) and \e depth-first \e search (DFS).
298 320
*/
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300 322
/**
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@defgroup shortest_path Shortest Path Algorithms
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@ingroup algs
303 325
\brief Algorithms for finding shortest paths.
304 326

	
305 327
This group contains the algorithms for finding shortest paths in digraphs.
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 - \ref Dijkstra algorithm for finding shortest paths from a source node
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   when all arc lengths are non-negative.
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 - \ref BellmanFord "Bellman-Ford" algorithm for finding shortest paths
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   from a source node when arc lenghts can be either positive or negative,
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   but the digraph should not contain directed cycles with negative total
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   length.
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 - \ref FloydWarshall "Floyd-Warshall" and \ref Johnson "Johnson" algorithms
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   for solving the \e all-pairs \e shortest \e paths \e problem when arc
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   lenghts can be either positive or negative, but the digraph should
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   not contain directed cycles with negative total length.
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 - \ref Suurballe A successive shortest path algorithm for finding
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   arc-disjoint paths between two nodes having minimum total length.
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*/
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321 343
/**
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@defgroup spantree Minimum Spanning Tree Algorithms
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@ingroup algs
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\brief Algorithms for finding minimum cost spanning trees and arborescences.
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This group contains the algorithms for finding minimum cost spanning
349
trees and arborescences.
350
*/
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/**
322 353
@defgroup max_flow Maximum Flow Algorithms
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@ingroup algs
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\brief Algorithms for finding maximum flows.
325 356

	
326 357
This group contains the algorithms for finding maximum flows and
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feasible circulations.
328 359

	
329 360
The \e maximum \e flow \e problem is to find a flow of maximum value between
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a single source and a single target. Formally, there is a \f$G=(V,A)\f$
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digraph, a \f$cap: A\rightarrow\mathbf{R}^+_0\f$ capacity function and
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\f$s, t \in V\f$ source and target nodes.
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A maximum flow is an \f$f: A\rightarrow\mathbf{R}^+_0\f$ solution of the
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following optimization problem.
335 366

	
336 367
\f[ \max\sum_{sv\in A} f(sv) - \sum_{vs\in A} f(vs) \f]
337 368
\f[ \sum_{uv\in A} f(uv) = \sum_{vu\in A} f(vu)
338 369
    \quad \forall u\in V\setminus\{s,t\} \f]
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\f[ 0 \leq f(uv) \leq cap(uv) \quad \forall uv\in A \f]
340 371

	
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LEMON contains several algorithms for solving maximum flow problems:
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- \ref EdmondsKarp Edmonds-Karp algorithm.
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- \ref Preflow Goldberg-Tarjan's preflow push-relabel algorithm.
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- \ref DinitzSleatorTarjan Dinitz's blocking flow algorithm with dynamic trees.
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- \ref GoldbergTarjan Preflow push-relabel algorithm with dynamic trees.
346 377

	
347 378
In most cases the \ref Preflow "Preflow" algorithm provides the
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fastest method for computing a maximum flow. All implementations
349 380
also provide functions to query the minimum cut, which is the dual
350 381
problem of maximum flow.
351 382

	
352 383
\ref Circulation is a preflow push-relabel algorithm implemented directly 
353 384
for finding feasible circulations, which is a somewhat different problem,
354 385
but it is strongly related to maximum flow.
355 386
For more information, see \ref Circulation.
356 387
*/
357 388

	
358 389
/**
359 390
@defgroup min_cost_flow_algs Minimum Cost Flow Algorithms
360 391
@ingroup algs
361 392

	
362 393
\brief Algorithms for finding minimum cost flows and circulations.
363 394

	
364 395
This group contains the algorithms for finding minimum cost flows and
365 396
circulations. For more information about this problem and its dual
366 397
solution see \ref min_cost_flow "Minimum Cost Flow Problem".
367 398

	
368 399
LEMON contains several algorithms for this problem.
369 400
 - \ref NetworkSimplex Primal Network Simplex algorithm with various
370 401
   pivot strategies.
371 402
 - \ref CostScaling Push-Relabel and Augment-Relabel algorithms based on
372 403
   cost scaling.
373 404
 - \ref CapacityScaling Successive Shortest %Path algorithm with optional
374 405
   capacity scaling.
375 406
 - \ref CancelAndTighten The Cancel and Tighten algorithm.
376 407
 - \ref CycleCanceling Cycle-Canceling algorithms.
377 408

	
378 409
In general NetworkSimplex is the most efficient implementation,
379 410
but in special cases other algorithms could be faster.
380 411
For example, if the total supply and/or capacities are rather small,
381 412
CapacityScaling is usually the fastest algorithm (without effective scaling).
382 413
*/
383 414

	
384 415
/**
385 416
@defgroup min_cut Minimum Cut Algorithms
386 417
@ingroup algs
387 418

	
388 419
\brief Algorithms for finding minimum cut in graphs.
389 420

	
390 421
This group contains the algorithms for finding minimum cut in graphs.
391 422

	
392 423
The \e minimum \e cut \e problem is to find a non-empty and non-complete
393 424
\f$X\f$ subset of the nodes with minimum overall capacity on
394 425
outgoing arcs. Formally, there is a \f$G=(V,A)\f$ digraph, a
395 426
\f$cap: A\rightarrow\mathbf{R}^+_0\f$ capacity function. The minimum
396 427
cut is the \f$X\f$ solution of the next optimization problem:
397 428

	
398 429
\f[ \min_{X \subset V, X\not\in \{\emptyset, V\}}
399
    \sum_{uv\in A, u\in X, v\not\in X}cap(uv) \f]
430
    \sum_{uv\in A: u\in X, v\not\in X}cap(uv) \f]
400 431

	
401 432
LEMON contains several algorithms related to minimum cut problems:
402 433

	
403 434
- \ref HaoOrlin "Hao-Orlin algorithm" for calculating minimum cut
404 435
  in directed graphs.
405 436
- \ref NagamochiIbaraki "Nagamochi-Ibaraki algorithm" for
406 437
  calculating minimum cut in undirected graphs.
407 438
- \ref GomoryHu "Gomory-Hu tree computation" for calculating
408 439
  all-pairs minimum cut in undirected graphs.
409 440

	
410 441
If you want to find minimum cut just between two distinict nodes,
411 442
see the \ref max_flow "maximum flow problem".
412 443
*/
413 444

	
414 445
/**
415
@defgroup graph_properties Connectivity and Other Graph Properties
416
@ingroup algs
417
\brief Algorithms for discovering the graph properties
418

	
419
This group contains the algorithms for discovering the graph properties
420
like connectivity, bipartiteness, euler property, simplicity etc.
421

	
422
\image html edge_biconnected_components.png
423
\image latex edge_biconnected_components.eps "bi-edge-connected components" width=\textwidth
424
*/
425

	
426
/**
427
@defgroup planar Planarity Embedding and Drawing
428
@ingroup algs
429
\brief Algorithms for planarity checking, embedding and drawing
430

	
431
This group contains the algorithms for planarity checking,
432
embedding and drawing.
433

	
434
\image html planar.png
435
\image latex planar.eps "Plane graph" width=\textwidth
436
*/
437

	
438
/**
439 446
@defgroup matching Matching Algorithms
440 447
@ingroup algs
441 448
\brief Algorithms for finding matchings in graphs and bipartite graphs.
442 449

	
443 450
This group contains the algorithms for calculating
444 451
matchings in graphs and bipartite graphs. The general matching problem is
445 452
finding a subset of the edges for which each node has at most one incident
446 453
edge.
447 454

	
448 455
There are several different algorithms for calculate matchings in
449 456
graphs.  The matching problems in bipartite graphs are generally
450 457
easier than in general graphs. The goal of the matching optimization
451 458
can be finding maximum cardinality, maximum weight or minimum cost
452 459
matching. The search can be constrained to find perfect or
453 460
maximum cardinality matching.
454 461

	
455 462
The matching algorithms implemented in LEMON:
456 463
- \ref MaxBipartiteMatching Hopcroft-Karp augmenting path algorithm
457 464
  for calculating maximum cardinality matching in bipartite graphs.
458 465
- \ref PrBipartiteMatching Push-relabel algorithm
459 466
  for calculating maximum cardinality matching in bipartite graphs.
460 467
- \ref MaxWeightedBipartiteMatching
461 468
  Successive shortest path algorithm for calculating maximum weighted
462 469
  matching and maximum weighted bipartite matching in bipartite graphs.
463 470
- \ref MinCostMaxBipartiteMatching
464 471
  Successive shortest path algorithm for calculating minimum cost maximum
465 472
  matching in bipartite graphs.
466 473
- \ref MaxMatching Edmond's blossom shrinking algorithm for calculating
467 474
  maximum cardinality matching in general graphs.
468 475
- \ref MaxWeightedMatching Edmond's blossom shrinking algorithm for calculating
469 476
  maximum weighted matching in general graphs.
470 477
- \ref MaxWeightedPerfectMatching
471 478
  Edmond's blossom shrinking algorithm for calculating maximum weighted
472 479
  perfect matching in general graphs.
473 480

	
474 481
\image html bipartite_matching.png
475 482
\image latex bipartite_matching.eps "Bipartite Matching" width=\textwidth
476 483
*/
477 484

	
478 485
/**
479
@defgroup spantree Minimum Spanning Tree Algorithms
486
@defgroup graph_properties Connectivity and Other Graph Properties
480 487
@ingroup algs
481
\brief Algorithms for finding minimum cost spanning trees and arborescences.
488
\brief Algorithms for discovering the graph properties
482 489

	
483
This group contains the algorithms for finding minimum cost spanning
484
trees and arborescences.
490
This group contains the algorithms for discovering the graph properties
491
like connectivity, bipartiteness, euler property, simplicity etc.
492

	
493
\image html connected_components.png
494
\image latex connected_components.eps "Connected components" width=\textwidth
495
*/
496

	
497
/**
498
@defgroup planar Planarity Embedding and Drawing
499
@ingroup algs
500
\brief Algorithms for planarity checking, embedding and drawing
501

	
502
This group contains the algorithms for planarity checking,
503
embedding and drawing.
504

	
505
\image html planar.png
506
\image latex planar.eps "Plane graph" width=\textwidth
507
*/
508

	
509
/**
510
@defgroup approx Approximation Algorithms
511
@ingroup algs
512
\brief Approximation algorithms.
513

	
514
This group contains the approximation and heuristic algorithms
515
implemented in LEMON.
485 516
*/
486 517

	
487 518
/**
488 519
@defgroup auxalg Auxiliary Algorithms
489 520
@ingroup algs
490 521
\brief Auxiliary algorithms implemented in LEMON.
491 522

	
492 523
This group contains some algorithms implemented in LEMON
493 524
in order to make it easier to implement complex algorithms.
494 525
*/
495 526

	
496 527
/**
497
@defgroup approx Approximation Algorithms
498
@ingroup algs
499
\brief Approximation algorithms.
500

	
501
This group contains the approximation and heuristic algorithms
502
implemented in LEMON.
503
*/
504

	
505
/**
506 528
@defgroup gen_opt_group General Optimization Tools
507 529
\brief This group contains some general optimization frameworks
508 530
implemented in LEMON.
509 531

	
510 532
This group contains some general optimization frameworks
511 533
implemented in LEMON.
512 534
*/
513 535

	
514 536
/**
515 537
@defgroup lp_group Lp and Mip Solvers
516 538
@ingroup gen_opt_group
517 539
\brief Lp and Mip solver interfaces for LEMON.
518 540

	
519 541
This group contains Lp and Mip solver interfaces for LEMON. The
520 542
various LP solvers could be used in the same manner with this
521 543
interface.
522 544
*/
523 545

	
524 546
/**
525 547
@defgroup lp_utils Tools for Lp and Mip Solvers
526 548
@ingroup lp_group
527 549
\brief Helper tools to the Lp and Mip solvers.
528 550

	
529 551
This group adds some helper tools to general optimization framework
530 552
implemented in LEMON.
531 553
*/
532 554

	
533 555
/**
534 556
@defgroup metah Metaheuristics
535 557
@ingroup gen_opt_group
536 558
\brief Metaheuristics for LEMON library.
537 559

	
538 560
This group contains some metaheuristic optimization tools.
539 561
*/
540 562

	
541 563
/**
542 564
@defgroup utils Tools and Utilities
543 565
\brief Tools and utilities for programming in LEMON
544 566

	
545 567
Tools and utilities for programming in LEMON.
546 568
*/
547 569

	
548 570
/**
549 571
@defgroup gutils Basic Graph Utilities
550 572
@ingroup utils
551 573
\brief Simple basic graph utilities.
552 574

	
553 575
This group contains some simple basic graph utilities.
554 576
*/
555 577

	
556 578
/**
557 579
@defgroup misc Miscellaneous Tools
558 580
@ingroup utils
559 581
\brief Tools for development, debugging and testing.
560 582

	
561 583
This group contains several useful tools for development,
562 584
debugging and testing.
563 585
*/
564 586

	
565 587
/**
566 588
@defgroup timecount Time Measuring and Counting
567 589
@ingroup misc
568 590
\brief Simple tools for measuring the performance of algorithms.
569 591

	
570 592
This group contains simple tools for measuring the performance
571 593
of algorithms.
572 594
*/
573 595

	
574 596
/**
575 597
@defgroup exceptions Exceptions
576 598
@ingroup utils
577 599
\brief Exceptions defined in LEMON.
578 600

	
579 601
This group contains the exceptions defined in LEMON.
580 602
*/
581 603

	
582 604
/**
583 605
@defgroup io_group Input-Output
584 606
\brief Graph Input-Output methods
585 607

	
586 608
This group contains the tools for importing and exporting graphs
587 609
and graph related data. Now it supports the \ref lgf-format
588 610
"LEMON Graph Format", the \c DIMACS format and the encapsulated
589 611
postscript (EPS) format.
590 612
*/
591 613

	
592 614
/**
593 615
@defgroup lemon_io LEMON Graph Format
594 616
@ingroup io_group
595 617
\brief Reading and writing LEMON Graph Format.
596 618

	
597 619
This group contains methods for reading and writing
598 620
\ref lgf-format "LEMON Graph Format".
599 621
*/
600 622

	
601 623
/**
602 624
@defgroup eps_io Postscript Exporting
603 625
@ingroup io_group
604 626
\brief General \c EPS drawer and graph exporter
605 627

	
606 628
This group contains general \c EPS drawing methods and special
607 629
graph exporting tools.
608 630
*/
609 631

	
610 632
/**
611
@defgroup dimacs_group DIMACS format
633
@defgroup dimacs_group DIMACS Format
612 634
@ingroup io_group
613 635
\brief Read and write files in DIMACS format
614 636

	
615 637
Tools to read a digraph from or write it to a file in DIMACS format data.
616 638
*/
617 639

	
618 640
/**
619 641
@defgroup nauty_group NAUTY Format
620 642
@ingroup io_group
621 643
\brief Read \e Nauty format
622 644

	
623 645
Tool to read graphs from \e Nauty format data.
624 646
*/
625 647

	
626 648
/**
627 649
@defgroup concept Concepts
628 650
\brief Skeleton classes and concept checking classes
629 651

	
630 652
This group contains the data/algorithm skeletons and concept checking
631 653
classes implemented in LEMON.
632 654

	
633 655
The purpose of the classes in this group is fourfold.
634 656

	
635 657
- These classes contain the documentations of the %concepts. In order
636 658
  to avoid document multiplications, an implementation of a concept
637 659
  simply refers to the corresponding concept class.
638 660

	
639 661
- These classes declare every functions, <tt>typedef</tt>s etc. an
640 662
  implementation of the %concepts should provide, however completely
641 663
  without implementations and real data structures behind the
642 664
  interface. On the other hand they should provide nothing else. All
643 665
  the algorithms working on a data structure meeting a certain concept
644 666
  should compile with these classes. (Though it will not run properly,
645 667
  of course.) In this way it is easily to check if an algorithm
646 668
  doesn't use any extra feature of a certain implementation.
647 669

	
648 670
- The concept descriptor classes also provide a <em>checker class</em>
649 671
  that makes it possible to check whether a certain implementation of a
650 672
  concept indeed provides all the required features.
651 673

	
652 674
- Finally, They can serve as a skeleton of a new implementation of a concept.
653 675
*/
654 676

	
655 677
/**
656 678
@defgroup graph_concepts Graph Structure Concepts
657 679
@ingroup concept
658 680
\brief Skeleton and concept checking classes for graph structures
659 681

	
660 682
This group contains the skeletons and concept checking classes of LEMON's
661 683
graph structures and helper classes used to implement these.
662 684
*/
663 685

	
664 686
/**
665 687
@defgroup map_concepts Map Concepts
666 688
@ingroup concept
667 689
\brief Skeleton and concept checking classes for maps
668 690

	
669 691
This group contains the skeletons and concept checking classes of maps.
670 692
*/
671 693

	
672 694
/**
695
@defgroup tools Standalone Utility Applications
696

	
697
Some utility applications are listed here.
698

	
699
The standard compilation procedure (<tt>./configure;make</tt>) will compile
700
them, as well.
701
*/
702

	
703
/**
673 704
\anchor demoprograms
674 705

	
675 706
@defgroup demos Demo Programs
676 707

	
677 708
Some demo programs are listed here. Their full source codes can be found in
678 709
the \c demo subdirectory of the source tree.
679 710

	
680 711
In order to compile them, use the <tt>make demo</tt> or the
681 712
<tt>make check</tt> commands.
682 713
*/
683 714

	
684
/**
685
@defgroup tools Standalone Utility Applications
686

	
687
Some utility applications are listed here.
688

	
689
The standard compilation procedure (<tt>./configure;make</tt>) will compile
690
them, as well.
691
*/
692

	
693 715
}
Ignore white space 768 line context
1 1
/* -*- mode: C++; indent-tabs-mode: nil; -*-
2 2
 *
3 3
 * This file is a part of LEMON, a generic C++ optimization library.
4 4
 *
5 5
 * Copyright (C) 2003-2009
6 6
 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 7
 * (Egervary Research Group on Combinatorial Optimization, EGRES).
8 8
 *
9 9
 * Permission to use, modify and distribute this software is granted
10 10
 * provided that this copyright notice appears in all copies. For
11 11
 * precise terms see the accompanying LICENSE file.
12 12
 *
13 13
 * This software is provided "AS IS" with no warranty of any kind,
14 14
 * express or implied, and with no claim as to its suitability for any
15 15
 * purpose.
16 16
 *
17 17
 */
18 18

	
19 19
#ifndef LEMON_BFS_H
20 20
#define LEMON_BFS_H
21 21

	
22 22
///\ingroup search
23 23
///\file
24 24
///\brief BFS algorithm.
25 25

	
26 26
#include <lemon/list_graph.h>
27 27
#include <lemon/bits/path_dump.h>
28 28
#include <lemon/core.h>
29 29
#include <lemon/error.h>
30 30
#include <lemon/maps.h>
31 31
#include <lemon/path.h>
32 32

	
33 33
namespace lemon {
34 34

	
35 35
  ///Default traits class of Bfs class.
36 36

	
37 37
  ///Default traits class of Bfs class.
38 38
  ///\tparam GR Digraph type.
39 39
  template<class GR>
40 40
  struct BfsDefaultTraits
41 41
  {
42 42
    ///The type of the digraph the algorithm runs on.
43 43
    typedef GR Digraph;
44 44

	
45 45
    ///\brief The type of the map that stores the predecessor
46 46
    ///arcs of the shortest paths.
47 47
    ///
48 48
    ///The type of the map that stores the predecessor
49 49
    ///arcs of the shortest paths.
50
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
50
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
51 51
    typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap;
52 52
    ///Instantiates a \c PredMap.
53 53

	
54 54
    ///This function instantiates a \ref PredMap.
55 55
    ///\param g is the digraph, to which we would like to define the
56 56
    ///\ref PredMap.
57 57
    static PredMap *createPredMap(const Digraph &g)
58 58
    {
59 59
      return new PredMap(g);
60 60
    }
61 61

	
62 62
    ///The type of the map that indicates which nodes are processed.
63 63

	
64 64
    ///The type of the map that indicates which nodes are processed.
65
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
65
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
66
    ///By default it is a NullMap.
66 67
    typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
67 68
    ///Instantiates a \c ProcessedMap.
68 69

	
69 70
    ///This function instantiates a \ref ProcessedMap.
70 71
    ///\param g is the digraph, to which
71 72
    ///we would like to define the \ref ProcessedMap
72 73
#ifdef DOXYGEN
73 74
    static ProcessedMap *createProcessedMap(const Digraph &g)
74 75
#else
75 76
    static ProcessedMap *createProcessedMap(const Digraph &)
76 77
#endif
77 78
    {
78 79
      return new ProcessedMap();
79 80
    }
80 81

	
81 82
    ///The type of the map that indicates which nodes are reached.
82 83

	
83 84
    ///The type of the map that indicates which nodes are reached.
84
    ///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
85
    ///It must conform to the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
85 86
    typedef typename Digraph::template NodeMap<bool> ReachedMap;
86 87
    ///Instantiates a \c ReachedMap.
87 88

	
88 89
    ///This function instantiates a \ref ReachedMap.
89 90
    ///\param g is the digraph, to which
90 91
    ///we would like to define the \ref ReachedMap.
91 92
    static ReachedMap *createReachedMap(const Digraph &g)
92 93
    {
93 94
      return new ReachedMap(g);
94 95
    }
95 96

	
96 97
    ///The type of the map that stores the distances of the nodes.
97 98

	
98 99
    ///The type of the map that stores the distances of the nodes.
99
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
100
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
100 101
    typedef typename Digraph::template NodeMap<int> DistMap;
101 102
    ///Instantiates a \c DistMap.
102 103

	
103 104
    ///This function instantiates a \ref DistMap.
104 105
    ///\param g is the digraph, to which we would like to define the
105 106
    ///\ref DistMap.
106 107
    static DistMap *createDistMap(const Digraph &g)
107 108
    {
108 109
      return new DistMap(g);
109 110
    }
110 111
  };
111 112

	
112 113
  ///%BFS algorithm class.
113 114

	
114 115
  ///\ingroup search
115 116
  ///This class provides an efficient implementation of the %BFS algorithm.
116 117
  ///
117 118
  ///There is also a \ref bfs() "function-type interface" for the BFS
118 119
  ///algorithm, which is convenient in the simplier cases and it can be
119 120
  ///used easier.
120 121
  ///
121 122
  ///\tparam GR The type of the digraph the algorithm runs on.
122 123
  ///The default type is \ref ListDigraph.
123 124
#ifdef DOXYGEN
124 125
  template <typename GR,
125 126
            typename TR>
126 127
#else
127 128
  template <typename GR=ListDigraph,
128 129
            typename TR=BfsDefaultTraits<GR> >
129 130
#endif
130 131
  class Bfs {
131 132
  public:
132 133

	
133 134
    ///The type of the digraph the algorithm runs on.
134 135
    typedef typename TR::Digraph Digraph;
135 136

	
136 137
    ///\brief The type of the map that stores the predecessor arcs of the
137 138
    ///shortest paths.
138 139
    typedef typename TR::PredMap PredMap;
139 140
    ///The type of the map that stores the distances of the nodes.
140 141
    typedef typename TR::DistMap DistMap;
141 142
    ///The type of the map that indicates which nodes are reached.
142 143
    typedef typename TR::ReachedMap ReachedMap;
143 144
    ///The type of the map that indicates which nodes are processed.
144 145
    typedef typename TR::ProcessedMap ProcessedMap;
145 146
    ///The type of the paths.
146 147
    typedef PredMapPath<Digraph, PredMap> Path;
147 148

	
148 149
    ///The \ref BfsDefaultTraits "traits class" of the algorithm.
149 150
    typedef TR Traits;
150 151

	
151 152
  private:
152 153

	
153 154
    typedef typename Digraph::Node Node;
154 155
    typedef typename Digraph::NodeIt NodeIt;
155 156
    typedef typename Digraph::Arc Arc;
156 157
    typedef typename Digraph::OutArcIt OutArcIt;
157 158

	
158 159
    //Pointer to the underlying digraph.
159 160
    const Digraph *G;
160 161
    //Pointer to the map of predecessor arcs.
161 162
    PredMap *_pred;
162 163
    //Indicates if _pred is locally allocated (true) or not.
163 164
    bool local_pred;
164 165
    //Pointer to the map of distances.
165 166
    DistMap *_dist;
166 167
    //Indicates if _dist is locally allocated (true) or not.
167 168
    bool local_dist;
168 169
    //Pointer to the map of reached status of the nodes.
169 170
    ReachedMap *_reached;
170 171
    //Indicates if _reached is locally allocated (true) or not.
171 172
    bool local_reached;
172 173
    //Pointer to the map of processed status of the nodes.
173 174
    ProcessedMap *_processed;
174 175
    //Indicates if _processed is locally allocated (true) or not.
175 176
    bool local_processed;
176 177

	
177 178
    std::vector<typename Digraph::Node> _queue;
178 179
    int _queue_head,_queue_tail,_queue_next_dist;
179 180
    int _curr_dist;
180 181

	
181 182
    //Creates the maps if necessary.
182 183
    void create_maps()
183 184
    {
184 185
      if(!_pred) {
185 186
        local_pred = true;
186 187
        _pred = Traits::createPredMap(*G);
187 188
      }
188 189
      if(!_dist) {
189 190
        local_dist = true;
190 191
        _dist = Traits::createDistMap(*G);
191 192
      }
192 193
      if(!_reached) {
193 194
        local_reached = true;
194 195
        _reached = Traits::createReachedMap(*G);
195 196
      }
196 197
      if(!_processed) {
197 198
        local_processed = true;
198 199
        _processed = Traits::createProcessedMap(*G);
199 200
      }
200 201
    }
201 202

	
202 203
  protected:
203 204

	
204 205
    Bfs() {}
205 206

	
206 207
  public:
207 208

	
208 209
    typedef Bfs Create;
209 210

	
210 211
    ///\name Named Template Parameters
211 212

	
212 213
    ///@{
213 214

	
214 215
    template <class T>
215 216
    struct SetPredMapTraits : public Traits {
216 217
      typedef T PredMap;
217 218
      static PredMap *createPredMap(const Digraph &)
218 219
      {
219 220
        LEMON_ASSERT(false, "PredMap is not initialized");
220 221
        return 0; // ignore warnings
221 222
      }
222 223
    };
223 224
    ///\brief \ref named-templ-param "Named parameter" for setting
224 225
    ///\c PredMap type.
225 226
    ///
226 227
    ///\ref named-templ-param "Named parameter" for setting
227 228
    ///\c PredMap type.
228
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
229
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
229 230
    template <class T>
230 231
    struct SetPredMap : public Bfs< Digraph, SetPredMapTraits<T> > {
231 232
      typedef Bfs< Digraph, SetPredMapTraits<T> > Create;
232 233
    };
233 234

	
234 235
    template <class T>
235 236
    struct SetDistMapTraits : public Traits {
236 237
      typedef T DistMap;
237 238
      static DistMap *createDistMap(const Digraph &)
238 239
      {
239 240
        LEMON_ASSERT(false, "DistMap is not initialized");
240 241
        return 0; // ignore warnings
241 242
      }
242 243
    };
243 244
    ///\brief \ref named-templ-param "Named parameter" for setting
244 245
    ///\c DistMap type.
245 246
    ///
246 247
    ///\ref named-templ-param "Named parameter" for setting
247 248
    ///\c DistMap type.
248
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
249
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
249 250
    template <class T>
250 251
    struct SetDistMap : public Bfs< Digraph, SetDistMapTraits<T> > {
251 252
      typedef Bfs< Digraph, SetDistMapTraits<T> > Create;
252 253
    };
253 254

	
254 255
    template <class T>
255 256
    struct SetReachedMapTraits : public Traits {
256 257
      typedef T ReachedMap;
257 258
      static ReachedMap *createReachedMap(const Digraph &)
258 259
      {
259 260
        LEMON_ASSERT(false, "ReachedMap is not initialized");
260 261
        return 0; // ignore warnings
261 262
      }
262 263
    };
263 264
    ///\brief \ref named-templ-param "Named parameter" for setting
264 265
    ///\c ReachedMap type.
265 266
    ///
266 267
    ///\ref named-templ-param "Named parameter" for setting
267 268
    ///\c ReachedMap type.
268
    ///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
269
    ///It must conform to the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
269 270
    template <class T>
270 271
    struct SetReachedMap : public Bfs< Digraph, SetReachedMapTraits<T> > {
271 272
      typedef Bfs< Digraph, SetReachedMapTraits<T> > Create;
272 273
    };
273 274

	
274 275
    template <class T>
275 276
    struct SetProcessedMapTraits : public Traits {
276 277
      typedef T ProcessedMap;
277 278
      static ProcessedMap *createProcessedMap(const Digraph &)
278 279
      {
279 280
        LEMON_ASSERT(false, "ProcessedMap is not initialized");
280 281
        return 0; // ignore warnings
281 282
      }
282 283
    };
283 284
    ///\brief \ref named-templ-param "Named parameter" for setting
284 285
    ///\c ProcessedMap type.
285 286
    ///
286 287
    ///\ref named-templ-param "Named parameter" for setting
287 288
    ///\c ProcessedMap type.
288
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
289
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
289 290
    template <class T>
290 291
    struct SetProcessedMap : public Bfs< Digraph, SetProcessedMapTraits<T> > {
291 292
      typedef Bfs< Digraph, SetProcessedMapTraits<T> > Create;
292 293
    };
293 294

	
294 295
    struct SetStandardProcessedMapTraits : public Traits {
295 296
      typedef typename Digraph::template NodeMap<bool> ProcessedMap;
296 297
      static ProcessedMap *createProcessedMap(const Digraph &g)
297 298
      {
298 299
        return new ProcessedMap(g);
299 300
        return 0; // ignore warnings
300 301
      }
301 302
    };
302 303
    ///\brief \ref named-templ-param "Named parameter" for setting
303 304
    ///\c ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>.
304 305
    ///
305 306
    ///\ref named-templ-param "Named parameter" for setting
306 307
    ///\c ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>.
307 308
    ///If you don't set it explicitly, it will be automatically allocated.
308 309
    struct SetStandardProcessedMap :
309 310
      public Bfs< Digraph, SetStandardProcessedMapTraits > {
310 311
      typedef Bfs< Digraph, SetStandardProcessedMapTraits > Create;
311 312
    };
312 313

	
313 314
    ///@}
314 315

	
315 316
  public:
316 317

	
317 318
    ///Constructor.
318 319

	
319 320
    ///Constructor.
320 321
    ///\param g The digraph the algorithm runs on.
321 322
    Bfs(const Digraph &g) :
322 323
      G(&g),
323 324
      _pred(NULL), local_pred(false),
324 325
      _dist(NULL), local_dist(false),
325 326
      _reached(NULL), local_reached(false),
326 327
      _processed(NULL), local_processed(false)
327 328
    { }
328 329

	
329 330
    ///Destructor.
330 331
    ~Bfs()
331 332
    {
332 333
      if(local_pred) delete _pred;
333 334
      if(local_dist) delete _dist;
334 335
      if(local_reached) delete _reached;
335 336
      if(local_processed) delete _processed;
336 337
    }
337 338

	
338 339
    ///Sets the map that stores the predecessor arcs.
339 340

	
340 341
    ///Sets the map that stores the predecessor arcs.
341 342
    ///If you don't use this function before calling \ref run(Node) "run()"
342 343
    ///or \ref init(), an instance will be allocated automatically.
343 344
    ///The destructor deallocates this automatically allocated map,
344 345
    ///of course.
345 346
    ///\return <tt> (*this) </tt>
346 347
    Bfs &predMap(PredMap &m)
347 348
    {
348 349
      if(local_pred) {
349 350
        delete _pred;
350 351
        local_pred=false;
351 352
      }
352 353
      _pred = &m;
353 354
      return *this;
354 355
    }
355 356

	
356 357
    ///Sets the map that indicates which nodes are reached.
357 358

	
358 359
    ///Sets the map that indicates which nodes are reached.
359 360
    ///If you don't use this function before calling \ref run(Node) "run()"
360 361
    ///or \ref init(), an instance will be allocated automatically.
361 362
    ///The destructor deallocates this automatically allocated map,
362 363
    ///of course.
363 364
    ///\return <tt> (*this) </tt>
364 365
    Bfs &reachedMap(ReachedMap &m)
365 366
    {
366 367
      if(local_reached) {
367 368
        delete _reached;
368 369
        local_reached=false;
369 370
      }
370 371
      _reached = &m;
371 372
      return *this;
372 373
    }
373 374

	
374 375
    ///Sets the map that indicates which nodes are processed.
375 376

	
376 377
    ///Sets the map that indicates which nodes are processed.
377 378
    ///If you don't use this function before calling \ref run(Node) "run()"
378 379
    ///or \ref init(), an instance will be allocated automatically.
379 380
    ///The destructor deallocates this automatically allocated map,
380 381
    ///of course.
381 382
    ///\return <tt> (*this) </tt>
382 383
    Bfs &processedMap(ProcessedMap &m)
383 384
    {
384 385
      if(local_processed) {
385 386
        delete _processed;
386 387
        local_processed=false;
387 388
      }
388 389
      _processed = &m;
389 390
      return *this;
390 391
    }
391 392

	
392 393
    ///Sets the map that stores the distances of the nodes.
393 394

	
394 395
    ///Sets the map that stores the distances of the nodes calculated by
395 396
    ///the algorithm.
396 397
    ///If you don't use this function before calling \ref run(Node) "run()"
397 398
    ///or \ref init(), an instance will be allocated automatically.
398 399
    ///The destructor deallocates this automatically allocated map,
399 400
    ///of course.
400 401
    ///\return <tt> (*this) </tt>
401 402
    Bfs &distMap(DistMap &m)
402 403
    {
403 404
      if(local_dist) {
404 405
        delete _dist;
405 406
        local_dist=false;
406 407
      }
407 408
      _dist = &m;
408 409
      return *this;
409 410
    }
410 411

	
411 412
  public:
412 413

	
413 414
    ///\name Execution Control
414 415
    ///The simplest way to execute the BFS algorithm is to use one of the
415 416
    ///member functions called \ref run(Node) "run()".\n
416
    ///If you need more control on the execution, first you have to call
417
    ///\ref init(), then you can add several source nodes with
417
    ///If you need better control on the execution, you have to call
418
    ///\ref init() first, then you can add several source nodes with
418 419
    ///\ref addSource(). Finally the actual path computation can be
419 420
    ///performed with one of the \ref start() functions.
420 421

	
421 422
    ///@{
422 423

	
423 424
    ///\brief Initializes the internal data structures.
424 425
    ///
425 426
    ///Initializes the internal data structures.
426 427
    void init()
427 428
    {
428 429
      create_maps();
429 430
      _queue.resize(countNodes(*G));
430 431
      _queue_head=_queue_tail=0;
431 432
      _curr_dist=1;
432 433
      for ( NodeIt u(*G) ; u!=INVALID ; ++u ) {
433 434
        _pred->set(u,INVALID);
434 435
        _reached->set(u,false);
435 436
        _processed->set(u,false);
436 437
      }
437 438
    }
438 439

	
439 440
    ///Adds a new source node.
440 441

	
441 442
    ///Adds a new source node to the set of nodes to be processed.
442 443
    ///
443 444
    void addSource(Node s)
444 445
    {
445 446
      if(!(*_reached)[s])
446 447
        {
447 448
          _reached->set(s,true);
448 449
          _pred->set(s,INVALID);
449 450
          _dist->set(s,0);
450 451
          _queue[_queue_head++]=s;
451 452
          _queue_next_dist=_queue_head;
452 453
        }
453 454
    }
454 455

	
455 456
    ///Processes the next node.
456 457

	
457 458
    ///Processes the next node.
458 459
    ///
459 460
    ///\return The processed node.
460 461
    ///
461 462
    ///\pre The queue must not be empty.
462 463
    Node processNextNode()
463 464
    {
464 465
      if(_queue_tail==_queue_next_dist) {
465 466
        _curr_dist++;
466 467
        _queue_next_dist=_queue_head;
467 468
      }
468 469
      Node n=_queue[_queue_tail++];
469 470
      _processed->set(n,true);
470 471
      Node m;
471 472
      for(OutArcIt e(*G,n);e!=INVALID;++e)
472 473
        if(!(*_reached)[m=G->target(e)]) {
473 474
          _queue[_queue_head++]=m;
474 475
          _reached->set(m,true);
475 476
          _pred->set(m,e);
476 477
          _dist->set(m,_curr_dist);
477 478
        }
478 479
      return n;
479 480
    }
480 481

	
481 482
    ///Processes the next node.
482 483

	
483 484
    ///Processes the next node and checks if the given target node
484 485
    ///is reached. If the target node is reachable from the processed
485 486
    ///node, then the \c reach parameter will be set to \c true.
486 487
    ///
487 488
    ///\param target The target node.
488 489
    ///\retval reach Indicates if the target node is reached.
489 490
    ///It should be initially \c false.
490 491
    ///
491 492
    ///\return The processed node.
492 493
    ///
493 494
    ///\pre The queue must not be empty.
494 495
    Node processNextNode(Node target, bool& reach)
495 496
    {
496 497
      if(_queue_tail==_queue_next_dist) {
497 498
        _curr_dist++;
498 499
        _queue_next_dist=_queue_head;
499 500
      }
500 501
      Node n=_queue[_queue_tail++];
501 502
      _processed->set(n,true);
502 503
      Node m;
503 504
      for(OutArcIt e(*G,n);e!=INVALID;++e)
504 505
        if(!(*_reached)[m=G->target(e)]) {
505 506
          _queue[_queue_head++]=m;
506 507
          _reached->set(m,true);
507 508
          _pred->set(m,e);
508 509
          _dist->set(m,_curr_dist);
509 510
          reach = reach || (target == m);
510 511
        }
511 512
      return n;
512 513
    }
513 514

	
514 515
    ///Processes the next node.
515 516

	
516 517
    ///Processes the next node and checks if at least one of reached
517 518
    ///nodes has \c true value in the \c nm node map. If one node
518 519
    ///with \c true value is reachable from the processed node, then the
519 520
    ///\c rnode parameter will be set to the first of such nodes.
520 521
    ///
521 522
    ///\param nm A \c bool (or convertible) node map that indicates the
522 523
    ///possible targets.
523 524
    ///\retval rnode The reached target node.
524 525
    ///It should be initially \c INVALID.
525 526
    ///
526 527
    ///\return The processed node.
527 528
    ///
528 529
    ///\pre The queue must not be empty.
529 530
    template<class NM>
530 531
    Node processNextNode(const NM& nm, Node& rnode)
531 532
    {
532 533
      if(_queue_tail==_queue_next_dist) {
533 534
        _curr_dist++;
534 535
        _queue_next_dist=_queue_head;
535 536
      }
536 537
      Node n=_queue[_queue_tail++];
537 538
      _processed->set(n,true);
538 539
      Node m;
539 540
      for(OutArcIt e(*G,n);e!=INVALID;++e)
540 541
        if(!(*_reached)[m=G->target(e)]) {
541 542
          _queue[_queue_head++]=m;
542 543
          _reached->set(m,true);
543 544
          _pred->set(m,e);
544 545
          _dist->set(m,_curr_dist);
545 546
          if (nm[m] && rnode == INVALID) rnode = m;
546 547
        }
547 548
      return n;
548 549
    }
549 550

	
550 551
    ///The next node to be processed.
551 552

	
552 553
    ///Returns the next node to be processed or \c INVALID if the queue
553 554
    ///is empty.
554 555
    Node nextNode() const
555 556
    {
556 557
      return _queue_tail<_queue_head?_queue[_queue_tail]:INVALID;
557 558
    }
558 559

	
559 560
    ///Returns \c false if there are nodes to be processed.
560 561

	
561 562
    ///Returns \c false if there are nodes to be processed
562 563
    ///in the queue.
563 564
    bool emptyQueue() const { return _queue_tail==_queue_head; }
564 565

	
565 566
    ///Returns the number of the nodes to be processed.
566 567

	
567 568
    ///Returns the number of the nodes to be processed
568 569
    ///in the queue.
569 570
    int queueSize() const { return _queue_head-_queue_tail; }
570 571

	
571 572
    ///Executes the algorithm.
572 573

	
573 574
    ///Executes the algorithm.
574 575
    ///
575 576
    ///This method runs the %BFS algorithm from the root node(s)
576 577
    ///in order to compute the shortest path to each node.
577 578
    ///
578 579
    ///The algorithm computes
579 580
    ///- the shortest path tree (forest),
580 581
    ///- the distance of each node from the root(s).
581 582
    ///
582 583
    ///\pre init() must be called and at least one root node should be
583 584
    ///added with addSource() before using this function.
584 585
    ///
585 586
    ///\note <tt>b.start()</tt> is just a shortcut of the following code.
586 587
    ///\code
587 588
    ///  while ( !b.emptyQueue() ) {
588 589
    ///    b.processNextNode();
589 590
    ///  }
590 591
    ///\endcode
591 592
    void start()
592 593
    {
593 594
      while ( !emptyQueue() ) processNextNode();
594 595
    }
595 596

	
596 597
    ///Executes the algorithm until the given target node is reached.
597 598

	
598 599
    ///Executes the algorithm until the given target node is reached.
599 600
    ///
600 601
    ///This method runs the %BFS algorithm from the root node(s)
601 602
    ///in order to compute the shortest path to \c t.
602 603
    ///
603 604
    ///The algorithm computes
604 605
    ///- the shortest path to \c t,
605 606
    ///- the distance of \c t from the root(s).
606 607
    ///
607 608
    ///\pre init() must be called and at least one root node should be
608 609
    ///added with addSource() before using this function.
609 610
    ///
610 611
    ///\note <tt>b.start(t)</tt> is just a shortcut of the following code.
611 612
    ///\code
612 613
    ///  bool reach = false;
613 614
    ///  while ( !b.emptyQueue() && !reach ) {
614 615
    ///    b.processNextNode(t, reach);
615 616
    ///  }
616 617
    ///\endcode
617 618
    void start(Node t)
618 619
    {
619 620
      bool reach = false;
620 621
      while ( !emptyQueue() && !reach ) processNextNode(t, reach);
621 622
    }
622 623

	
623 624
    ///Executes the algorithm until a condition is met.
624 625

	
625 626
    ///Executes the algorithm until a condition is met.
626 627
    ///
627 628
    ///This method runs the %BFS algorithm from the root node(s) in
628 629
    ///order to compute the shortest path to a node \c v with
629 630
    /// <tt>nm[v]</tt> true, if such a node can be found.
630 631
    ///
631 632
    ///\param nm A \c bool (or convertible) node map. The algorithm
632 633
    ///will stop when it reaches a node \c v with <tt>nm[v]</tt> true.
633 634
    ///
634 635
    ///\return The reached node \c v with <tt>nm[v]</tt> true or
635 636
    ///\c INVALID if no such node was found.
636 637
    ///
637 638
    ///\pre init() must be called and at least one root node should be
638 639
    ///added with addSource() before using this function.
639 640
    ///
640 641
    ///\note <tt>b.start(nm)</tt> is just a shortcut of the following code.
641 642
    ///\code
642 643
    ///  Node rnode = INVALID;
643 644
    ///  while ( !b.emptyQueue() && rnode == INVALID ) {
644 645
    ///    b.processNextNode(nm, rnode);
645 646
    ///  }
646 647
    ///  return rnode;
647 648
    ///\endcode
648 649
    template<class NodeBoolMap>
649 650
    Node start(const NodeBoolMap &nm)
650 651
    {
651 652
      Node rnode = INVALID;
652 653
      while ( !emptyQueue() && rnode == INVALID ) {
653 654
        processNextNode(nm, rnode);
654 655
      }
655 656
      return rnode;
656 657
    }
657 658

	
658 659
    ///Runs the algorithm from the given source node.
659 660

	
660 661
    ///This method runs the %BFS algorithm from node \c s
661 662
    ///in order to compute the shortest path to each node.
662 663
    ///
663 664
    ///The algorithm computes
664 665
    ///- the shortest path tree,
665 666
    ///- the distance of each node from the root.
666 667
    ///
667 668
    ///\note <tt>b.run(s)</tt> is just a shortcut of the following code.
668 669
    ///\code
669 670
    ///  b.init();
670 671
    ///  b.addSource(s);
671 672
    ///  b.start();
672 673
    ///\endcode
673 674
    void run(Node s) {
674 675
      init();
675 676
      addSource(s);
676 677
      start();
677 678
    }
678 679

	
679 680
    ///Finds the shortest path between \c s and \c t.
680 681

	
681 682
    ///This method runs the %BFS algorithm from node \c s
682 683
    ///in order to compute the shortest path to node \c t
683 684
    ///(it stops searching when \c t is processed).
684 685
    ///
685 686
    ///\return \c true if \c t is reachable form \c s.
686 687
    ///
687 688
    ///\note Apart from the return value, <tt>b.run(s,t)</tt> is just a
688 689
    ///shortcut of the following code.
689 690
    ///\code
690 691
    ///  b.init();
691 692
    ///  b.addSource(s);
692 693
    ///  b.start(t);
693 694
    ///\endcode
694 695
    bool run(Node s,Node t) {
695 696
      init();
696 697
      addSource(s);
697 698
      start(t);
698 699
      return reached(t);
699 700
    }
700 701

	
701 702
    ///Runs the algorithm to visit all nodes in the digraph.
702 703

	
703 704
    ///This method runs the %BFS algorithm in order to
704 705
    ///compute the shortest path to each node.
705 706
    ///
706 707
    ///The algorithm computes
707 708
    ///- the shortest path tree (forest),
708 709
    ///- the distance of each node from the root(s).
709 710
    ///
710 711
    ///\note <tt>b.run(s)</tt> is just a shortcut of the following code.
711 712
    ///\code
712 713
    ///  b.init();
713 714
    ///  for (NodeIt n(gr); n != INVALID; ++n) {
714 715
    ///    if (!b.reached(n)) {
715 716
    ///      b.addSource(n);
716 717
    ///      b.start();
717 718
    ///    }
718 719
    ///  }
719 720
    ///\endcode
720 721
    void run() {
721 722
      init();
722 723
      for (NodeIt n(*G); n != INVALID; ++n) {
723 724
        if (!reached(n)) {
724 725
          addSource(n);
725 726
          start();
726 727
        }
727 728
      }
728 729
    }
729 730

	
730 731
    ///@}
731 732

	
732 733
    ///\name Query Functions
733 734
    ///The results of the BFS algorithm can be obtained using these
734 735
    ///functions.\n
735 736
    ///Either \ref run(Node) "run()" or \ref start() should be called
736 737
    ///before using them.
737 738

	
738 739
    ///@{
739 740

	
740
    ///The shortest path to a node.
741
    ///The shortest path to the given node.
741 742

	
742
    ///Returns the shortest path to a node.
743
    ///Returns the shortest path to the given node from the root(s).
743 744
    ///
744 745
    ///\warning \c t should be reached from the root(s).
745 746
    ///
746 747
    ///\pre Either \ref run(Node) "run()" or \ref init()
747 748
    ///must be called before using this function.
748 749
    Path path(Node t) const { return Path(*G, *_pred, t); }
749 750

	
750
    ///The distance of a node from the root(s).
751
    ///The distance of the given node from the root(s).
751 752

	
752
    ///Returns the distance of a node from the root(s).
753
    ///Returns the distance of the given node from the root(s).
753 754
    ///
754 755
    ///\warning If node \c v is not reached from the root(s), then
755 756
    ///the return value of this function is undefined.
756 757
    ///
757 758
    ///\pre Either \ref run(Node) "run()" or \ref init()
758 759
    ///must be called before using this function.
759 760
    int dist(Node v) const { return (*_dist)[v]; }
760 761

	
761
    ///Returns the 'previous arc' of the shortest path tree for a node.
762

	
762
    ///\brief Returns the 'previous arc' of the shortest path tree for
763
    ///the given node.
764
    ///
763 765
    ///This function returns the 'previous arc' of the shortest path
764 766
    ///tree for the node \c v, i.e. it returns the last arc of a
765 767
    ///shortest path from a root to \c v. It is \c INVALID if \c v
766 768
    ///is not reached from the root(s) or if \c v is a root.
767 769
    ///
768 770
    ///The shortest path tree used here is equal to the shortest path
769
    ///tree used in \ref predNode().
771
    ///tree used in \ref predNode() and \ref predMap().
770 772
    ///
771 773
    ///\pre Either \ref run(Node) "run()" or \ref init()
772 774
    ///must be called before using this function.
773 775
    Arc predArc(Node v) const { return (*_pred)[v];}
774 776

	
775
    ///Returns the 'previous node' of the shortest path tree for a node.
776

	
777
    ///\brief Returns the 'previous node' of the shortest path tree for
778
    ///the given node.
779
    ///
777 780
    ///This function returns the 'previous node' of the shortest path
778 781
    ///tree for the node \c v, i.e. it returns the last but one node
779
    ///from a shortest path from a root to \c v. It is \c INVALID
782
    ///of a shortest path from a root to \c v. It is \c INVALID
780 783
    ///if \c v is not reached from the root(s) or if \c v is a root.
781 784
    ///
782 785
    ///The shortest path tree used here is equal to the shortest path
783
    ///tree used in \ref predArc().
786
    ///tree used in \ref predArc() and \ref predMap().
784 787
    ///
785 788
    ///\pre Either \ref run(Node) "run()" or \ref init()
786 789
    ///must be called before using this function.
787 790
    Node predNode(Node v) const { return (*_pred)[v]==INVALID ? INVALID:
788 791
                                  G->source((*_pred)[v]); }
789 792

	
790 793
    ///\brief Returns a const reference to the node map that stores the
791 794
    /// distances of the nodes.
792 795
    ///
793 796
    ///Returns a const reference to the node map that stores the distances
794 797
    ///of the nodes calculated by the algorithm.
795 798
    ///
796 799
    ///\pre Either \ref run(Node) "run()" or \ref init()
797 800
    ///must be called before using this function.
798 801
    const DistMap &distMap() const { return *_dist;}
799 802

	
800 803
    ///\brief Returns a const reference to the node map that stores the
801 804
    ///predecessor arcs.
802 805
    ///
803 806
    ///Returns a const reference to the node map that stores the predecessor
804
    ///arcs, which form the shortest path tree.
807
    ///arcs, which form the shortest path tree (forest).
805 808
    ///
806 809
    ///\pre Either \ref run(Node) "run()" or \ref init()
807 810
    ///must be called before using this function.
808 811
    const PredMap &predMap() const { return *_pred;}
809 812

	
810
    ///Checks if a node is reached from the root(s).
813
    ///Checks if the given node is reached from the root(s).
811 814

	
812 815
    ///Returns \c true if \c v is reached from the root(s).
813 816
    ///
814 817
    ///\pre Either \ref run(Node) "run()" or \ref init()
815 818
    ///must be called before using this function.
816 819
    bool reached(Node v) const { return (*_reached)[v]; }
817 820

	
818 821
    ///@}
819 822
  };
820 823

	
821 824
  ///Default traits class of bfs() function.
822 825

	
823 826
  ///Default traits class of bfs() function.
824 827
  ///\tparam GR Digraph type.
825 828
  template<class GR>
826 829
  struct BfsWizardDefaultTraits
827 830
  {
828 831
    ///The type of the digraph the algorithm runs on.
829 832
    typedef GR Digraph;
830 833

	
831 834
    ///\brief The type of the map that stores the predecessor
832 835
    ///arcs of the shortest paths.
833 836
    ///
834 837
    ///The type of the map that stores the predecessor
835 838
    ///arcs of the shortest paths.
836
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
839
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
837 840
    typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap;
838 841
    ///Instantiates a PredMap.
839 842

	
840 843
    ///This function instantiates a PredMap.
841 844
    ///\param g is the digraph, to which we would like to define the
842 845
    ///PredMap.
843 846
    static PredMap *createPredMap(const Digraph &g)
844 847
    {
845 848
      return new PredMap(g);
846 849
    }
847 850

	
848 851
    ///The type of the map that indicates which nodes are processed.
849 852

	
850 853
    ///The type of the map that indicates which nodes are processed.
851
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
854
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
852 855
    ///By default it is a NullMap.
853 856
    typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
854 857
    ///Instantiates a ProcessedMap.
855 858

	
856 859
    ///This function instantiates a ProcessedMap.
857 860
    ///\param g is the digraph, to which
858 861
    ///we would like to define the ProcessedMap.
859 862
#ifdef DOXYGEN
860 863
    static ProcessedMap *createProcessedMap(const Digraph &g)
861 864
#else
862 865
    static ProcessedMap *createProcessedMap(const Digraph &)
863 866
#endif
864 867
    {
865 868
      return new ProcessedMap();
866 869
    }
867 870

	
868 871
    ///The type of the map that indicates which nodes are reached.
869 872

	
870 873
    ///The type of the map that indicates which nodes are reached.
871
    ///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
874
    ///It must conform to the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
872 875
    typedef typename Digraph::template NodeMap<bool> ReachedMap;
873 876
    ///Instantiates a ReachedMap.
874 877

	
875 878
    ///This function instantiates a ReachedMap.
876 879
    ///\param g is the digraph, to which
877 880
    ///we would like to define the ReachedMap.
878 881
    static ReachedMap *createReachedMap(const Digraph &g)
879 882
    {
880 883
      return new ReachedMap(g);
881 884
    }
882 885

	
883 886
    ///The type of the map that stores the distances of the nodes.
884 887

	
885 888
    ///The type of the map that stores the distances of the nodes.
886
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
889
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
887 890
    typedef typename Digraph::template NodeMap<int> DistMap;
888 891
    ///Instantiates a DistMap.
889 892

	
890 893
    ///This function instantiates a DistMap.
891 894
    ///\param g is the digraph, to which we would like to define
892 895
    ///the DistMap
893 896
    static DistMap *createDistMap(const Digraph &g)
894 897
    {
895 898
      return new DistMap(g);
896 899
    }
897 900

	
898 901
    ///The type of the shortest paths.
899 902

	
900 903
    ///The type of the shortest paths.
901
    ///It must meet the \ref concepts::Path "Path" concept.
904
    ///It must conform to the \ref concepts::Path "Path" concept.
902 905
    typedef lemon::Path<Digraph> Path;
903 906
  };
904 907

	
905 908
  /// Default traits class used by BfsWizard
906 909

	
907
  /// To make it easier to use Bfs algorithm
908
  /// we have created a wizard class.
909
  /// This \ref BfsWizard class needs default traits,
910
  /// as well as the \ref Bfs class.
911
  /// The \ref BfsWizardBase is a class to be the default traits of the
912
  /// \ref BfsWizard class.
910
  /// Default traits class used by BfsWizard.
911
  /// \tparam GR The type of the digraph.
913 912
  template<class GR>
914 913
  class BfsWizardBase : public BfsWizardDefaultTraits<GR>
915 914
  {
916 915

	
917 916
    typedef BfsWizardDefaultTraits<GR> Base;
918 917
  protected:
919 918
    //The type of the nodes in the digraph.
920 919
    typedef typename Base::Digraph::Node Node;
921 920

	
922 921
    //Pointer to the digraph the algorithm runs on.
923 922
    void *_g;
924 923
    //Pointer to the map of reached nodes.
925 924
    void *_reached;
926 925
    //Pointer to the map of processed nodes.
927 926
    void *_processed;
928 927
    //Pointer to the map of predecessors arcs.
929 928
    void *_pred;
930 929
    //Pointer to the map of distances.
931 930
    void *_dist;
932 931
    //Pointer to the shortest path to the target node.
933 932
    void *_path;
934 933
    //Pointer to the distance of the target node.
935 934
    int *_di;
936 935

	
937 936
    public:
938 937
    /// Constructor.
939 938

	
940
    /// This constructor does not require parameters, therefore it initiates
939
    /// This constructor does not require parameters, it initiates
941 940
    /// all of the attributes to \c 0.
942 941
    BfsWizardBase() : _g(0), _reached(0), _processed(0), _pred(0),
943 942
                      _dist(0), _path(0), _di(0) {}
944 943

	
945 944
    /// Constructor.
946 945

	
947 946
    /// This constructor requires one parameter,
948 947
    /// others are initiated to \c 0.
949 948
    /// \param g The digraph the algorithm runs on.
950 949
    BfsWizardBase(const GR &g) :
951 950
      _g(reinterpret_cast<void*>(const_cast<GR*>(&g))),
952 951
      _reached(0), _processed(0), _pred(0), _dist(0),  _path(0), _di(0) {}
953 952

	
954 953
  };
955 954

	
956 955
  /// Auxiliary class for the function-type interface of BFS algorithm.
957 956

	
958 957
  /// This auxiliary class is created to implement the
959 958
  /// \ref bfs() "function-type interface" of \ref Bfs algorithm.
960 959
  /// It does not have own \ref run(Node) "run()" method, it uses the
961 960
  /// functions and features of the plain \ref Bfs.
962 961
  ///
963 962
  /// This class should only be used through the \ref bfs() function,
964 963
  /// which makes it easier to use the algorithm.
965 964
  template<class TR>
966 965
  class BfsWizard : public TR
967 966
  {
968 967
    typedef TR Base;
969 968

	
970
    ///The type of the digraph the algorithm runs on.
971 969
    typedef typename TR::Digraph Digraph;
972 970

	
973 971
    typedef typename Digraph::Node Node;
974 972
    typedef typename Digraph::NodeIt NodeIt;
975 973
    typedef typename Digraph::Arc Arc;
976 974
    typedef typename Digraph::OutArcIt OutArcIt;
977 975

	
978
    ///\brief The type of the map that stores the predecessor
979
    ///arcs of the shortest paths.
980 976
    typedef typename TR::PredMap PredMap;
981
    ///\brief The type of the map that stores the distances of the nodes.
982 977
    typedef typename TR::DistMap DistMap;
983
    ///\brief The type of the map that indicates which nodes are reached.
984 978
    typedef typename TR::ReachedMap ReachedMap;
985
    ///\brief The type of the map that indicates which nodes are processed.
986 979
    typedef typename TR::ProcessedMap ProcessedMap;
987
    ///The type of the shortest paths
988 980
    typedef typename TR::Path Path;
989 981

	
990 982
  public:
991 983

	
992 984
    /// Constructor.
993 985
    BfsWizard() : TR() {}
994 986

	
995 987
    /// Constructor that requires parameters.
996 988

	
997 989
    /// Constructor that requires parameters.
998 990
    /// These parameters will be the default values for the traits class.
999 991
    /// \param g The digraph the algorithm runs on.
1000 992
    BfsWizard(const Digraph &g) :
1001 993
      TR(g) {}
1002 994

	
1003 995
    ///Copy constructor
1004 996
    BfsWizard(const TR &b) : TR(b) {}
1005 997

	
1006 998
    ~BfsWizard() {}
1007 999

	
1008 1000
    ///Runs BFS algorithm from the given source node.
1009 1001

	
1010 1002
    ///This method runs BFS algorithm from node \c s
1011 1003
    ///in order to compute the shortest path to each node.
1012 1004
    void run(Node s)
1013 1005
    {
1014 1006
      Bfs<Digraph,TR> alg(*reinterpret_cast<const Digraph*>(Base::_g));
1015 1007
      if (Base::_pred)
1016 1008
        alg.predMap(*reinterpret_cast<PredMap*>(Base::_pred));
1017 1009
      if (Base::_dist)
1018 1010
        alg.distMap(*reinterpret_cast<DistMap*>(Base::_dist));
1019 1011
      if (Base::_reached)
1020 1012
        alg.reachedMap(*reinterpret_cast<ReachedMap*>(Base::_reached));
1021 1013
      if (Base::_processed)
1022 1014
        alg.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed));
1023 1015
      if (s!=INVALID)
1024 1016
        alg.run(s);
1025 1017
      else
1026 1018
        alg.run();
1027 1019
    }
1028 1020

	
1029 1021
    ///Finds the shortest path between \c s and \c t.
1030 1022

	
1031 1023
    ///This method runs BFS algorithm from node \c s
1032 1024
    ///in order to compute the shortest path to node \c t
1033 1025
    ///(it stops searching when \c t is processed).
1034 1026
    ///
1035 1027
    ///\return \c true if \c t is reachable form \c s.
1036 1028
    bool run(Node s, Node t)
1037 1029
    {
1038 1030
      Bfs<Digraph,TR> alg(*reinterpret_cast<const Digraph*>(Base::_g));
1039 1031
      if (Base::_pred)
1040 1032
        alg.predMap(*reinterpret_cast<PredMap*>(Base::_pred));
1041 1033
      if (Base::_dist)
1042 1034
        alg.distMap(*reinterpret_cast<DistMap*>(Base::_dist));
1043 1035
      if (Base::_reached)
1044 1036
        alg.reachedMap(*reinterpret_cast<ReachedMap*>(Base::_reached));
1045 1037
      if (Base::_processed)
1046 1038
        alg.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed));
1047 1039
      alg.run(s,t);
1048 1040
      if (Base::_path)
1049 1041
        *reinterpret_cast<Path*>(Base::_path) = alg.path(t);
1050 1042
      if (Base::_di)
1051 1043
        *Base::_di = alg.dist(t);
1052 1044
      return alg.reached(t);
1053 1045
    }
1054 1046

	
1055 1047
    ///Runs BFS algorithm to visit all nodes in the digraph.
1056 1048

	
1057 1049
    ///This method runs BFS algorithm in order to compute
1058 1050
    ///the shortest path to each node.
1059 1051
    void run()
1060 1052
    {
1061 1053
      run(INVALID);
1062 1054
    }
1063 1055

	
1064 1056
    template<class T>
1065 1057
    struct SetPredMapBase : public Base {
1066 1058
      typedef T PredMap;
1067 1059
      static PredMap *createPredMap(const Digraph &) { return 0; };
1068 1060
      SetPredMapBase(const TR &b) : TR(b) {}
1069 1061
    };
1070
    ///\brief \ref named-func-param "Named parameter"
1071
    ///for setting PredMap object.
1062

	
1063
    ///\brief \ref named-templ-param "Named parameter" for setting
1064
    ///the predecessor map.
1072 1065
    ///
1073
    ///\ref named-func-param "Named parameter"
1074
    ///for setting PredMap object.
1066
    ///\ref named-templ-param "Named parameter" function for setting
1067
    ///the map that stores the predecessor arcs of the nodes.
1075 1068
    template<class T>
1076 1069
    BfsWizard<SetPredMapBase<T> > predMap(const T &t)
1077 1070
    {
1078 1071
      Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t));
1079 1072
      return BfsWizard<SetPredMapBase<T> >(*this);
1080 1073
    }
1081 1074

	
1082 1075
    template<class T>
1083 1076
    struct SetReachedMapBase : public Base {
1084 1077
      typedef T ReachedMap;
1085 1078
      static ReachedMap *createReachedMap(const Digraph &) { return 0; };
1086 1079
      SetReachedMapBase(const TR &b) : TR(b) {}
1087 1080
    };
1088
    ///\brief \ref named-func-param "Named parameter"
1089
    ///for setting ReachedMap object.
1081

	
1082
    ///\brief \ref named-templ-param "Named parameter" for setting
1083
    ///the reached map.
1090 1084
    ///
1091
    /// \ref named-func-param "Named parameter"
1092
    ///for setting ReachedMap object.
1085
    ///\ref named-templ-param "Named parameter" function for setting
1086
    ///the map that indicates which nodes are reached.
1093 1087
    template<class T>
1094 1088
    BfsWizard<SetReachedMapBase<T> > reachedMap(const T &t)
1095 1089
    {
1096 1090
      Base::_reached=reinterpret_cast<void*>(const_cast<T*>(&t));
1097 1091
      return BfsWizard<SetReachedMapBase<T> >(*this);
1098 1092
    }
1099 1093

	
1100 1094
    template<class T>
1101 1095
    struct SetDistMapBase : public Base {
1102 1096
      typedef T DistMap;
1103 1097
      static DistMap *createDistMap(const Digraph &) { return 0; };
1104 1098
      SetDistMapBase(const TR &b) : TR(b) {}
1105 1099
    };
1106
    ///\brief \ref named-func-param "Named parameter"
1107
    ///for setting DistMap object.
1100

	
1101
    ///\brief \ref named-templ-param "Named parameter" for setting
1102
    ///the distance map.
1108 1103
    ///
1109
    /// \ref named-func-param "Named parameter"
1110
    ///for setting DistMap object.
1104
    ///\ref named-templ-param "Named parameter" function for setting
1105
    ///the map that stores the distances of the nodes calculated
1106
    ///by the algorithm.
1111 1107
    template<class T>
1112 1108
    BfsWizard<SetDistMapBase<T> > distMap(const T &t)
1113 1109
    {
1114 1110
      Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t));
1115 1111
      return BfsWizard<SetDistMapBase<T> >(*this);
1116 1112
    }
1117 1113

	
1118 1114
    template<class T>
1119 1115
    struct SetProcessedMapBase : public Base {
1120 1116
      typedef T ProcessedMap;
1121 1117
      static ProcessedMap *createProcessedMap(const Digraph &) { return 0; };
1122 1118
      SetProcessedMapBase(const TR &b) : TR(b) {}
1123 1119
    };
1124
    ///\brief \ref named-func-param "Named parameter"
1125
    ///for setting ProcessedMap object.
1120

	
1121
    ///\brief \ref named-func-param "Named parameter" for setting
1122
    ///the processed map.
1126 1123
    ///
1127
    /// \ref named-func-param "Named parameter"
1128
    ///for setting ProcessedMap object.
1124
    ///\ref named-templ-param "Named parameter" function for setting
1125
    ///the map that indicates which nodes are processed.
1129 1126
    template<class T>
1130 1127
    BfsWizard<SetProcessedMapBase<T> > processedMap(const T &t)
1131 1128
    {
1132 1129
      Base::_processed=reinterpret_cast<void*>(const_cast<T*>(&t));
1133 1130
      return BfsWizard<SetProcessedMapBase<T> >(*this);
1134 1131
    }
1135 1132

	
1136 1133
    template<class T>
1137 1134
    struct SetPathBase : public Base {
1138 1135
      typedef T Path;
1139 1136
      SetPathBase(const TR &b) : TR(b) {}
1140 1137
    };
1141 1138
    ///\brief \ref named-func-param "Named parameter"
1142 1139
    ///for getting the shortest path to the target node.
1143 1140
    ///
1144 1141
    ///\ref named-func-param "Named parameter"
1145 1142
    ///for getting the shortest path to the target node.
1146 1143
    template<class T>
1147 1144
    BfsWizard<SetPathBase<T> > path(const T &t)
1148 1145
    {
1149 1146
      Base::_path=reinterpret_cast<void*>(const_cast<T*>(&t));
1150 1147
      return BfsWizard<SetPathBase<T> >(*this);
1151 1148
    }
1152 1149

	
1153 1150
    ///\brief \ref named-func-param "Named parameter"
1154 1151
    ///for getting the distance of the target node.
1155 1152
    ///
1156 1153
    ///\ref named-func-param "Named parameter"
1157 1154
    ///for getting the distance of the target node.
1158 1155
    BfsWizard dist(const int &d)
1159 1156
    {
1160 1157
      Base::_di=const_cast<int*>(&d);
1161 1158
      return *this;
1162 1159
    }
1163 1160

	
1164 1161
  };
1165 1162

	
1166 1163
  ///Function-type interface for BFS algorithm.
1167 1164

	
1168 1165
  /// \ingroup search
1169 1166
  ///Function-type interface for BFS algorithm.
1170 1167
  ///
1171 1168
  ///This function also has several \ref named-func-param "named parameters",
1172 1169
  ///they are declared as the members of class \ref BfsWizard.
1173 1170
  ///The following examples show how to use these parameters.
1174 1171
  ///\code
1175 1172
  ///  // Compute shortest path from node s to each node
1176 1173
  ///  bfs(g).predMap(preds).distMap(dists).run(s);
1177 1174
  ///
1178 1175
  ///  // Compute shortest path from s to t
1179 1176
  ///  bool reached = bfs(g).path(p).dist(d).run(s,t);
1180 1177
  ///\endcode
1181 1178
  ///\warning Don't forget to put the \ref BfsWizard::run(Node) "run()"
1182 1179
  ///to the end of the parameter list.
1183 1180
  ///\sa BfsWizard
1184 1181
  ///\sa Bfs
1185 1182
  template<class GR>
1186 1183
  BfsWizard<BfsWizardBase<GR> >
1187 1184
  bfs(const GR &digraph)
1188 1185
  {
1189 1186
    return BfsWizard<BfsWizardBase<GR> >(digraph);
1190 1187
  }
1191 1188

	
1192 1189
#ifdef DOXYGEN
1193 1190
  /// \brief Visitor class for BFS.
1194 1191
  ///
1195 1192
  /// This class defines the interface of the BfsVisit events, and
1196 1193
  /// it could be the base of a real visitor class.
1197 1194
  template <typename GR>
1198 1195
  struct BfsVisitor {
1199 1196
    typedef GR Digraph;
1200 1197
    typedef typename Digraph::Arc Arc;
1201 1198
    typedef typename Digraph::Node Node;
1202 1199
    /// \brief Called for the source node(s) of the BFS.
1203 1200
    ///
1204 1201
    /// This function is called for the source node(s) of the BFS.
1205 1202
    void start(const Node& node) {}
1206 1203
    /// \brief Called when a node is reached first time.
1207 1204
    ///
1208 1205
    /// This function is called when a node is reached first time.
1209 1206
    void reach(const Node& node) {}
1210 1207
    /// \brief Called when a node is processed.
1211 1208
    ///
1212 1209
    /// This function is called when a node is processed.
1213 1210
    void process(const Node& node) {}
1214 1211
    /// \brief Called when an arc reaches a new node.
1215 1212
    ///
1216 1213
    /// This function is called when the BFS finds an arc whose target node
1217 1214
    /// is not reached yet.
1218 1215
    void discover(const Arc& arc) {}
1219 1216
    /// \brief Called when an arc is examined but its target node is
1220 1217
    /// already discovered.
1221 1218
    ///
1222 1219
    /// This function is called when an arc is examined but its target node is
1223 1220
    /// already discovered.
1224 1221
    void examine(const Arc& arc) {}
1225 1222
  };
1226 1223
#else
1227 1224
  template <typename GR>
1228 1225
  struct BfsVisitor {
1229 1226
    typedef GR Digraph;
1230 1227
    typedef typename Digraph::Arc Arc;
1231 1228
    typedef typename Digraph::Node Node;
1232 1229
    void start(const Node&) {}
1233 1230
    void reach(const Node&) {}
1234 1231
    void process(const Node&) {}
1235 1232
    void discover(const Arc&) {}
1236 1233
    void examine(const Arc&) {}
1237 1234

	
1238 1235
    template <typename _Visitor>
1239 1236
    struct Constraints {
1240 1237
      void constraints() {
1241 1238
        Arc arc;
1242 1239
        Node node;
1243 1240
        visitor.start(node);
1244 1241
        visitor.reach(node);
1245 1242
        visitor.process(node);
1246 1243
        visitor.discover(arc);
1247 1244
        visitor.examine(arc);
1248 1245
      }
1249 1246
      _Visitor& visitor;
1250 1247
    };
1251 1248
  };
1252 1249
#endif
1253 1250

	
1254 1251
  /// \brief Default traits class of BfsVisit class.
1255 1252
  ///
1256 1253
  /// Default traits class of BfsVisit class.
1257 1254
  /// \tparam GR The type of the digraph the algorithm runs on.
1258 1255
  template<class GR>
1259 1256
  struct BfsVisitDefaultTraits {
1260 1257

	
1261 1258
    /// \brief The type of the digraph the algorithm runs on.
1262 1259
    typedef GR Digraph;
1263 1260

	
1264 1261
    /// \brief The type of the map that indicates which nodes are reached.
1265 1262
    ///
1266 1263
    /// The type of the map that indicates which nodes are reached.
1267
    /// It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
1264
    /// It must conform to the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
1268 1265
    typedef typename Digraph::template NodeMap<bool> ReachedMap;
1269 1266

	
1270 1267
    /// \brief Instantiates a ReachedMap.
1271 1268
    ///
1272 1269
    /// This function instantiates a ReachedMap.
1273 1270
    /// \param digraph is the digraph, to which
1274 1271
    /// we would like to define the ReachedMap.
1275 1272
    static ReachedMap *createReachedMap(const Digraph &digraph) {
1276 1273
      return new ReachedMap(digraph);
1277 1274
    }
1278 1275

	
1279 1276
  };
1280 1277

	
1281 1278
  /// \ingroup search
1282 1279
  ///
1283 1280
  /// \brief BFS algorithm class with visitor interface.
1284 1281
  ///
1285 1282
  /// This class provides an efficient implementation of the BFS algorithm
1286 1283
  /// with visitor interface.
1287 1284
  ///
1288 1285
  /// The BfsVisit class provides an alternative interface to the Bfs
1289 1286
  /// class. It works with callback mechanism, the BfsVisit object calls
1290 1287
  /// the member functions of the \c Visitor class on every BFS event.
1291 1288
  ///
1292 1289
  /// This interface of the BFS algorithm should be used in special cases
1293 1290
  /// when extra actions have to be performed in connection with certain
1294 1291
  /// events of the BFS algorithm. Otherwise consider to use Bfs or bfs()
1295 1292
  /// instead.
1296 1293
  ///
1297 1294
  /// \tparam GR The type of the digraph the algorithm runs on.
1298 1295
  /// The default type is \ref ListDigraph.
1299 1296
  /// The value of GR is not used directly by \ref BfsVisit,
1300 1297
  /// it is only passed to \ref BfsVisitDefaultTraits.
1301 1298
  /// \tparam VS The Visitor type that is used by the algorithm.
1302 1299
  /// \ref BfsVisitor "BfsVisitor<GR>" is an empty visitor, which
1303 1300
  /// does not observe the BFS events. If you want to observe the BFS
1304 1301
  /// events, you should implement your own visitor class.
1305 1302
  /// \tparam TR Traits class to set various data types used by the
1306 1303
  /// algorithm. The default traits class is
1307 1304
  /// \ref BfsVisitDefaultTraits "BfsVisitDefaultTraits<GR>".
1308 1305
  /// See \ref BfsVisitDefaultTraits for the documentation of
1309 1306
  /// a BFS visit traits class.
1310 1307
#ifdef DOXYGEN
1311 1308
  template <typename GR, typename VS, typename TR>
1312 1309
#else
1313 1310
  template <typename GR = ListDigraph,
1314 1311
            typename VS = BfsVisitor<GR>,
1315 1312
            typename TR = BfsVisitDefaultTraits<GR> >
1316 1313
#endif
1317 1314
  class BfsVisit {
1318 1315
  public:
1319 1316

	
1320 1317
    ///The traits class.
1321 1318
    typedef TR Traits;
1322 1319

	
1323 1320
    ///The type of the digraph the algorithm runs on.
1324 1321
    typedef typename Traits::Digraph Digraph;
1325 1322

	
1326 1323
    ///The visitor type used by the algorithm.
1327 1324
    typedef VS Visitor;
1328 1325

	
1329 1326
    ///The type of the map that indicates which nodes are reached.
1330 1327
    typedef typename Traits::ReachedMap ReachedMap;
1331 1328

	
1332 1329
  private:
1333 1330

	
1334 1331
    typedef typename Digraph::Node Node;
1335 1332
    typedef typename Digraph::NodeIt NodeIt;
1336 1333
    typedef typename Digraph::Arc Arc;
1337 1334
    typedef typename Digraph::OutArcIt OutArcIt;
1338 1335

	
1339 1336
    //Pointer to the underlying digraph.
1340 1337
    const Digraph *_digraph;
1341 1338
    //Pointer to the visitor object.
1342 1339
    Visitor *_visitor;
1343 1340
    //Pointer to the map of reached status of the nodes.
1344 1341
    ReachedMap *_reached;
1345 1342
    //Indicates if _reached is locally allocated (true) or not.
1346 1343
    bool local_reached;
1347 1344

	
1348 1345
    std::vector<typename Digraph::Node> _list;
1349 1346
    int _list_front, _list_back;
1350 1347

	
1351 1348
    //Creates the maps if necessary.
1352 1349
    void create_maps() {
1353 1350
      if(!_reached) {
1354 1351
        local_reached = true;
1355 1352
        _reached = Traits::createReachedMap(*_digraph);
1356 1353
      }
1357 1354
    }
1358 1355

	
1359 1356
  protected:
1360 1357

	
1361 1358
    BfsVisit() {}
1362 1359

	
1363 1360
  public:
1364 1361

	
1365 1362
    typedef BfsVisit Create;
1366 1363

	
1367 1364
    /// \name Named Template Parameters
1368 1365

	
1369 1366
    ///@{
1370 1367
    template <class T>
1371 1368
    struct SetReachedMapTraits : public Traits {
1372 1369
      typedef T ReachedMap;
1373 1370
      static ReachedMap *createReachedMap(const Digraph &digraph) {
1374 1371
        LEMON_ASSERT(false, "ReachedMap is not initialized");
1375 1372
        return 0; // ignore warnings
1376 1373
      }
1377 1374
    };
1378 1375
    /// \brief \ref named-templ-param "Named parameter" for setting
1379 1376
    /// ReachedMap type.
1380 1377
    ///
1381 1378
    /// \ref named-templ-param "Named parameter" for setting ReachedMap type.
1382 1379
    template <class T>
1383 1380
    struct SetReachedMap : public BfsVisit< Digraph, Visitor,
1384 1381
                                            SetReachedMapTraits<T> > {
1385 1382
      typedef BfsVisit< Digraph, Visitor, SetReachedMapTraits<T> > Create;
1386 1383
    };
1387 1384
    ///@}
1388 1385

	
1389 1386
  public:
1390 1387

	
1391 1388
    /// \brief Constructor.
1392 1389
    ///
1393 1390
    /// Constructor.
1394 1391
    ///
1395 1392
    /// \param digraph The digraph the algorithm runs on.
1396 1393
    /// \param visitor The visitor object of the algorithm.
1397 1394
    BfsVisit(const Digraph& digraph, Visitor& visitor)
1398 1395
      : _digraph(&digraph), _visitor(&visitor),
1399 1396
        _reached(0), local_reached(false) {}
1400 1397

	
1401 1398
    /// \brief Destructor.
1402 1399
    ~BfsVisit() {
1403 1400
      if(local_reached) delete _reached;
1404 1401
    }
1405 1402

	
1406 1403
    /// \brief Sets the map that indicates which nodes are reached.
1407 1404
    ///
1408 1405
    /// Sets the map that indicates which nodes are reached.
1409 1406
    /// If you don't use this function before calling \ref run(Node) "run()"
1410 1407
    /// or \ref init(), an instance will be allocated automatically.
1411 1408
    /// The destructor deallocates this automatically allocated map,
1412 1409
    /// of course.
1413 1410
    /// \return <tt> (*this) </tt>
1414 1411
    BfsVisit &reachedMap(ReachedMap &m) {
1415 1412
      if(local_reached) {
1416 1413
        delete _reached;
1417 1414
        local_reached = false;
1418 1415
      }
1419 1416
      _reached = &m;
1420 1417
      return *this;
1421 1418
    }
1422 1419

	
1423 1420
  public:
1424 1421

	
1425 1422
    /// \name Execution Control
1426 1423
    /// The simplest way to execute the BFS algorithm is to use one of the
1427 1424
    /// member functions called \ref run(Node) "run()".\n
1428
    /// If you need more control on the execution, first you have to call
1429
    /// \ref init(), then you can add several source nodes with
1425
    /// If you need better control on the execution, you have to call
1426
    /// \ref init() first, then you can add several source nodes with
1430 1427
    /// \ref addSource(). Finally the actual path computation can be
1431 1428
    /// performed with one of the \ref start() functions.
1432 1429

	
1433 1430
    /// @{
1434 1431

	
1435 1432
    /// \brief Initializes the internal data structures.
1436 1433
    ///
1437 1434
    /// Initializes the internal data structures.
1438 1435
    void init() {
1439 1436
      create_maps();
1440 1437
      _list.resize(countNodes(*_digraph));
1441 1438
      _list_front = _list_back = -1;
1442 1439
      for (NodeIt u(*_digraph) ; u != INVALID ; ++u) {
1443 1440
        _reached->set(u, false);
1444 1441
      }
1445 1442
    }
1446 1443

	
1447 1444
    /// \brief Adds a new source node.
1448 1445
    ///
1449 1446
    /// Adds a new source node to the set of nodes to be processed.
1450 1447
    void addSource(Node s) {
1451 1448
      if(!(*_reached)[s]) {
1452 1449
          _reached->set(s,true);
1453 1450
          _visitor->start(s);
1454 1451
          _visitor->reach(s);
1455 1452
          _list[++_list_back] = s;
1456 1453
        }
1457 1454
    }
1458 1455

	
1459 1456
    /// \brief Processes the next node.
1460 1457
    ///
1461 1458
    /// Processes the next node.
1462 1459
    ///
1463 1460
    /// \return The processed node.
1464 1461
    ///
1465 1462
    /// \pre The queue must not be empty.
1466 1463
    Node processNextNode() {
1467 1464
      Node n = _list[++_list_front];
1468 1465
      _visitor->process(n);
1469 1466
      Arc e;
1470 1467
      for (_digraph->firstOut(e, n); e != INVALID; _digraph->nextOut(e)) {
1471 1468
        Node m = _digraph->target(e);
1472 1469
        if (!(*_reached)[m]) {
1473 1470
          _visitor->discover(e);
1474 1471
          _visitor->reach(m);
1475 1472
          _reached->set(m, true);
1476 1473
          _list[++_list_back] = m;
1477 1474
        } else {
1478 1475
          _visitor->examine(e);
1479 1476
        }
1480 1477
      }
1481 1478
      return n;
1482 1479
    }
1483 1480

	
1484 1481
    /// \brief Processes the next node.
1485 1482
    ///
1486 1483
    /// Processes the next node and checks if the given target node
1487 1484
    /// is reached. If the target node is reachable from the processed
1488 1485
    /// node, then the \c reach parameter will be set to \c true.
1489 1486
    ///
1490 1487
    /// \param target The target node.
1491 1488
    /// \retval reach Indicates if the target node is reached.
1492 1489
    /// It should be initially \c false.
1493 1490
    ///
1494 1491
    /// \return The processed node.
1495 1492
    ///
1496 1493
    /// \pre The queue must not be empty.
1497 1494
    Node processNextNode(Node target, bool& reach) {
1498 1495
      Node n = _list[++_list_front];
1499 1496
      _visitor->process(n);
1500 1497
      Arc e;
1501 1498
      for (_digraph->firstOut(e, n); e != INVALID; _digraph->nextOut(e)) {
1502 1499
        Node m = _digraph->target(e);
1503 1500
        if (!(*_reached)[m]) {
1504 1501
          _visitor->discover(e);
1505 1502
          _visitor->reach(m);
1506 1503
          _reached->set(m, true);
1507 1504
          _list[++_list_back] = m;
1508 1505
          reach = reach || (target == m);
1509 1506
        } else {
1510 1507
          _visitor->examine(e);
1511 1508
        }
1512 1509
      }
1513 1510
      return n;
1514 1511
    }
1515 1512

	
1516 1513
    /// \brief Processes the next node.
1517 1514
    ///
1518 1515
    /// Processes the next node and checks if at least one of reached
1519 1516
    /// nodes has \c true value in the \c nm node map. If one node
1520 1517
    /// with \c true value is reachable from the processed node, then the
1521 1518
    /// \c rnode parameter will be set to the first of such nodes.
1522 1519
    ///
1523 1520
    /// \param nm A \c bool (or convertible) node map that indicates the
1524 1521
    /// possible targets.
1525 1522
    /// \retval rnode The reached target node.
1526 1523
    /// It should be initially \c INVALID.
1527 1524
    ///
1528 1525
    /// \return The processed node.
1529 1526
    ///
1530 1527
    /// \pre The queue must not be empty.
1531 1528
    template <typename NM>
1532 1529
    Node processNextNode(const NM& nm, Node& rnode) {
1533 1530
      Node n = _list[++_list_front];
1534 1531
      _visitor->process(n);
1535 1532
      Arc e;
1536 1533
      for (_digraph->firstOut(e, n); e != INVALID; _digraph->nextOut(e)) {
1537 1534
        Node m = _digraph->target(e);
1538 1535
        if (!(*_reached)[m]) {
1539 1536
          _visitor->discover(e);
1540 1537
          _visitor->reach(m);
1541 1538
          _reached->set(m, true);
1542 1539
          _list[++_list_back] = m;
1543 1540
          if (nm[m] && rnode == INVALID) rnode = m;
1544 1541
        } else {
1545 1542
          _visitor->examine(e);
1546 1543
        }
1547 1544
      }
1548 1545
      return n;
1549 1546
    }
1550 1547

	
1551 1548
    /// \brief The next node to be processed.
1552 1549
    ///
1553 1550
    /// Returns the next node to be processed or \c INVALID if the queue
1554 1551
    /// is empty.
1555 1552
    Node nextNode() const {
1556 1553
      return _list_front != _list_back ? _list[_list_front + 1] : INVALID;
1557 1554
    }
1558 1555

	
1559 1556
    /// \brief Returns \c false if there are nodes
1560 1557
    /// to be processed.
1561 1558
    ///
1562 1559
    /// Returns \c false if there are nodes
1563 1560
    /// to be processed in the queue.
1564 1561
    bool emptyQueue() const { return _list_front == _list_back; }
1565 1562

	
1566 1563
    /// \brief Returns the number of the nodes to be processed.
1567 1564
    ///
1568 1565
    /// Returns the number of the nodes to be processed in the queue.
1569 1566
    int queueSize() const { return _list_back - _list_front; }
1570 1567

	
1571 1568
    /// \brief Executes the algorithm.
1572 1569
    ///
1573 1570
    /// Executes the algorithm.
1574 1571
    ///
1575 1572
    /// This method runs the %BFS algorithm from the root node(s)
1576 1573
    /// in order to compute the shortest path to each node.
1577 1574
    ///
1578 1575
    /// The algorithm computes
1579 1576
    /// - the shortest path tree (forest),
1580 1577
    /// - the distance of each node from the root(s).
1581 1578
    ///
1582 1579
    /// \pre init() must be called and at least one root node should be added
1583 1580
    /// with addSource() before using this function.
1584 1581
    ///
1585 1582
    /// \note <tt>b.start()</tt> is just a shortcut of the following code.
1586 1583
    /// \code
1587 1584
    ///   while ( !b.emptyQueue() ) {
1588 1585
    ///     b.processNextNode();
1589 1586
    ///   }
1590 1587
    /// \endcode
1591 1588
    void start() {
1592 1589
      while ( !emptyQueue() ) processNextNode();
1593 1590
    }
1594 1591

	
1595 1592
    /// \brief Executes the algorithm until the given target node is reached.
1596 1593
    ///
1597 1594
    /// Executes the algorithm until the given target node is reached.
1598 1595
    ///
1599 1596
    /// This method runs the %BFS algorithm from the root node(s)
1600 1597
    /// in order to compute the shortest path to \c t.
1601 1598
    ///
1602 1599
    /// The algorithm computes
1603 1600
    /// - the shortest path to \c t,
1604 1601
    /// - the distance of \c t from the root(s).
1605 1602
    ///
1606 1603
    /// \pre init() must be called and at least one root node should be
1607 1604
    /// added with addSource() before using this function.
1608 1605
    ///
1609 1606
    /// \note <tt>b.start(t)</tt> is just a shortcut of the following code.
1610 1607
    /// \code
1611 1608
    ///   bool reach = false;
1612 1609
    ///   while ( !b.emptyQueue() && !reach ) {
1613 1610
    ///     b.processNextNode(t, reach);
1614 1611
    ///   }
1615 1612
    /// \endcode
1616 1613
    void start(Node t) {
1617 1614
      bool reach = false;
1618 1615
      while ( !emptyQueue() && !reach ) processNextNode(t, reach);
1619 1616
    }
1620 1617

	
1621 1618
    /// \brief Executes the algorithm until a condition is met.
1622 1619
    ///
1623 1620
    /// Executes the algorithm until a condition is met.
1624 1621
    ///
1625 1622
    /// This method runs the %BFS algorithm from the root node(s) in
1626 1623
    /// order to compute the shortest path to a node \c v with
1627 1624
    /// <tt>nm[v]</tt> true, if such a node can be found.
1628 1625
    ///
1629 1626
    /// \param nm must be a bool (or convertible) node map. The
1630 1627
    /// algorithm will stop when it reaches a node \c v with
1631 1628
    /// <tt>nm[v]</tt> true.
1632 1629
    ///
1633 1630
    /// \return The reached node \c v with <tt>nm[v]</tt> true or
1634 1631
    /// \c INVALID if no such node was found.
1635 1632
    ///
1636 1633
    /// \pre init() must be called and at least one root node should be
1637 1634
    /// added with addSource() before using this function.
1638 1635
    ///
1639 1636
    /// \note <tt>b.start(nm)</tt> is just a shortcut of the following code.
1640 1637
    /// \code
1641 1638
    ///   Node rnode = INVALID;
1642 1639
    ///   while ( !b.emptyQueue() && rnode == INVALID ) {
1643 1640
    ///     b.processNextNode(nm, rnode);
1644 1641
    ///   }
1645 1642
    ///   return rnode;
1646 1643
    /// \endcode
1647 1644
    template <typename NM>
1648 1645
    Node start(const NM &nm) {
1649 1646
      Node rnode = INVALID;
1650 1647
      while ( !emptyQueue() && rnode == INVALID ) {
1651 1648
        processNextNode(nm, rnode);
1652 1649
      }
1653 1650
      return rnode;
1654 1651
    }
1655 1652

	
1656 1653
    /// \brief Runs the algorithm from the given source node.
1657 1654
    ///
1658 1655
    /// This method runs the %BFS algorithm from node \c s
1659 1656
    /// in order to compute the shortest path to each node.
1660 1657
    ///
1661 1658
    /// The algorithm computes
1662 1659
    /// - the shortest path tree,
1663 1660
    /// - the distance of each node from the root.
1664 1661
    ///
1665 1662
    /// \note <tt>b.run(s)</tt> is just a shortcut of the following code.
1666 1663
    ///\code
1667 1664
    ///   b.init();
1668 1665
    ///   b.addSource(s);
1669 1666
    ///   b.start();
1670 1667
    ///\endcode
1671 1668
    void run(Node s) {
1672 1669
      init();
1673 1670
      addSource(s);
1674 1671
      start();
1675 1672
    }
1676 1673

	
1677 1674
    /// \brief Finds the shortest path between \c s and \c t.
1678 1675
    ///
1679 1676
    /// This method runs the %BFS algorithm from node \c s
1680 1677
    /// in order to compute the shortest path to node \c t
1681 1678
    /// (it stops searching when \c t is processed).
1682 1679
    ///
1683 1680
    /// \return \c true if \c t is reachable form \c s.
1684 1681
    ///
1685 1682
    /// \note Apart from the return value, <tt>b.run(s,t)</tt> is just a
1686 1683
    /// shortcut of the following code.
1687 1684
    ///\code
1688 1685
    ///   b.init();
1689 1686
    ///   b.addSource(s);
1690 1687
    ///   b.start(t);
1691 1688
    ///\endcode
1692 1689
    bool run(Node s,Node t) {
1693 1690
      init();
1694 1691
      addSource(s);
1695 1692
      start(t);
1696 1693
      return reached(t);
1697 1694
    }
1698 1695

	
1699 1696
    /// \brief Runs the algorithm to visit all nodes in the digraph.
1700 1697
    ///
1701 1698
    /// This method runs the %BFS algorithm in order to
1702 1699
    /// compute the shortest path to each node.
1703 1700
    ///
1704 1701
    /// The algorithm computes
1705 1702
    /// - the shortest path tree (forest),
1706 1703
    /// - the distance of each node from the root(s).
1707 1704
    ///
1708 1705
    /// \note <tt>b.run(s)</tt> is just a shortcut of the following code.
1709 1706
    ///\code
1710 1707
    ///  b.init();
1711 1708
    ///  for (NodeIt n(gr); n != INVALID; ++n) {
1712 1709
    ///    if (!b.reached(n)) {
1713 1710
    ///      b.addSource(n);
1714 1711
    ///      b.start();
1715 1712
    ///    }
1716 1713
    ///  }
1717 1714
    ///\endcode
1718 1715
    void run() {
1719 1716
      init();
1720 1717
      for (NodeIt it(*_digraph); it != INVALID; ++it) {
1721 1718
        if (!reached(it)) {
1722 1719
          addSource(it);
1723 1720
          start();
1724 1721
        }
1725 1722
      }
1726 1723
    }
1727 1724

	
1728 1725
    ///@}
1729 1726

	
1730 1727
    /// \name Query Functions
1731 1728
    /// The results of the BFS algorithm can be obtained using these
1732 1729
    /// functions.\n
1733 1730
    /// Either \ref run(Node) "run()" or \ref start() should be called
1734 1731
    /// before using them.
1735 1732

	
1736 1733
    ///@{
1737 1734

	
1738
    /// \brief Checks if a node is reached from the root(s).
1735
    /// \brief Checks if the given node is reached from the root(s).
1739 1736
    ///
1740 1737
    /// Returns \c true if \c v is reached from the root(s).
1741 1738
    ///
1742 1739
    /// \pre Either \ref run(Node) "run()" or \ref init()
1743 1740
    /// must be called before using this function.
1744 1741
    bool reached(Node v) const { return (*_reached)[v]; }
1745 1742

	
1746 1743
    ///@}
1747 1744

	
1748 1745
  };
1749 1746

	
1750 1747
} //END OF NAMESPACE LEMON
1751 1748

	
1752 1749
#endif
Ignore white space 6 line context
1 1
/* -*- mode: C++; indent-tabs-mode: nil; -*-
2 2
 *
3 3
 * This file is a part of LEMON, a generic C++ optimization library.
4 4
 *
5 5
 * Copyright (C) 2003-2009
6 6
 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 7
 * (Egervary Research Group on Combinatorial Optimization, EGRES).
8 8
 *
9 9
 * Permission to use, modify and distribute this software is granted
10 10
 * provided that this copyright notice appears in all copies. For
11 11
 * precise terms see the accompanying LICENSE file.
12 12
 *
13 13
 * This software is provided "AS IS" with no warranty of any kind,
14 14
 * express or implied, and with no claim as to its suitability for any
15 15
 * purpose.
16 16
 *
17 17
 */
18 18

	
19 19
#ifndef LEMON_BITS_MAP_EXTENDER_H
20 20
#define LEMON_BITS_MAP_EXTENDER_H
21 21

	
22 22
#include <iterator>
23 23

	
24 24
#include <lemon/bits/traits.h>
25 25

	
26 26
#include <lemon/concept_check.h>
27 27
#include <lemon/concepts/maps.h>
28 28

	
29 29
//\file
30 30
//\brief Extenders for iterable maps.
31 31

	
32 32
namespace lemon {
33 33

	
34 34
  // \ingroup graphbits
35 35
  //
36 36
  // \brief Extender for maps
37 37
  template <typename _Map>
38 38
  class MapExtender : public _Map {
39 39
    typedef _Map Parent;
40 40
    typedef typename Parent::GraphType GraphType;
41 41

	
42 42
  public:
43 43

	
44 44
    typedef MapExtender Map;
45 45
    typedef typename Parent::Key Item;
46 46

	
47 47
    typedef typename Parent::Key Key;
48 48
    typedef typename Parent::Value Value;
49 49
    typedef typename Parent::Reference Reference;
50 50
    typedef typename Parent::ConstReference ConstReference;
51 51

	
52
    typedef typename Parent::ReferenceMapTag ReferenceMapTag;
53

	
52 54
    class MapIt;
53 55
    class ConstMapIt;
54 56

	
55 57
    friend class MapIt;
56 58
    friend class ConstMapIt;
57 59

	
58 60
  public:
59 61

	
60 62
    MapExtender(const GraphType& graph)
61 63
      : Parent(graph) {}
62 64

	
63 65
    MapExtender(const GraphType& graph, const Value& value)
64 66
      : Parent(graph, value) {}
65 67

	
66 68
  private:
67 69
    MapExtender& operator=(const MapExtender& cmap) {
68 70
      return operator=<MapExtender>(cmap);
69 71
    }
70 72

	
71 73
    template <typename CMap>
72 74
    MapExtender& operator=(const CMap& cmap) {
73 75
      Parent::operator=(cmap);
74 76
      return *this;
75 77
    }
76 78

	
77 79
  public:
78 80
    class MapIt : public Item {
79 81
      typedef Item Parent;
80 82

	
81 83
    public:
82 84

	
83 85
      typedef typename Map::Value Value;
84 86

	
85 87
      MapIt() {}
86 88

	
87 89
      MapIt(Invalid i) : Parent(i) { }
88 90

	
89 91
      explicit MapIt(Map& _map) : map(_map) {
90 92
        map.notifier()->first(*this);
91 93
      }
92 94

	
93 95
      MapIt(const Map& _map, const Item& item)
94 96
        : Parent(item), map(_map) {}
95 97

	
96 98
      MapIt& operator++() {
97 99
        map.notifier()->next(*this);
98 100
        return *this;
99 101
      }
100 102

	
101 103
      typename MapTraits<Map>::ConstReturnValue operator*() const {
102 104
        return map[*this];
103 105
      }
104 106

	
105 107
      typename MapTraits<Map>::ReturnValue operator*() {
106 108
        return map[*this];
107 109
      }
108 110

	
109 111
      void set(const Value& value) {
110 112
        map.set(*this, value);
111 113
      }
112 114

	
113 115
    protected:
114 116
      Map& map;
115 117

	
116 118
    };
117 119

	
118 120
    class ConstMapIt : public Item {
119 121
      typedef Item Parent;
120 122

	
121 123
    public:
122 124

	
123 125
      typedef typename Map::Value Value;
124 126

	
125 127
      ConstMapIt() {}
126 128

	
127 129
      ConstMapIt(Invalid i) : Parent(i) { }
128 130

	
129 131
      explicit ConstMapIt(Map& _map) : map(_map) {
130 132
        map.notifier()->first(*this);
131 133
      }
132 134

	
133 135
      ConstMapIt(const Map& _map, const Item& item)
134 136
        : Parent(item), map(_map) {}
135 137

	
136 138
      ConstMapIt& operator++() {
137 139
        map.notifier()->next(*this);
138 140
        return *this;
139 141
      }
140 142

	
141 143
      typename MapTraits<Map>::ConstReturnValue operator*() const {
142 144
        return map[*this];
143 145
      }
144 146

	
145 147
    protected:
146 148
      const Map& map;
147 149
    };
148 150

	
149 151
    class ItemIt : public Item {
150 152
      typedef Item Parent;
151 153

	
152 154
    public:
153 155

	
154 156
      ItemIt() {}
155 157

	
156 158
      ItemIt(Invalid i) : Parent(i) { }
157 159

	
158 160
      explicit ItemIt(Map& _map) : map(_map) {
159 161
        map.notifier()->first(*this);
160 162
      }
161 163

	
162 164
      ItemIt(const Map& _map, const Item& item)
163 165
        : Parent(item), map(_map) {}
164 166

	
165 167
      ItemIt& operator++() {
166 168
        map.notifier()->next(*this);
167 169
        return *this;
168 170
      }
169 171

	
170 172
    protected:
171 173
      const Map& map;
172 174

	
173 175
    };
174 176
  };
175 177

	
176 178
  // \ingroup graphbits
177 179
  //
178 180
  // \brief Extender for maps which use a subset of the items.
179 181
  template <typename _Graph, typename _Map>
180 182
  class SubMapExtender : public _Map {
181 183
    typedef _Map Parent;
182 184
    typedef _Graph GraphType;
183 185

	
184 186
  public:
185 187

	
186 188
    typedef SubMapExtender Map;
187 189
    typedef typename Parent::Key Item;
188 190

	
189 191
    typedef typename Parent::Key Key;
190 192
    typedef typename Parent::Value Value;
191 193
    typedef typename Parent::Reference Reference;
192 194
    typedef typename Parent::ConstReference ConstReference;
193 195

	
196
    typedef typename Parent::ReferenceMapTag ReferenceMapTag;
197

	
194 198
    class MapIt;
195 199
    class ConstMapIt;
196 200

	
197 201
    friend class MapIt;
198 202
    friend class ConstMapIt;
199 203

	
200 204
  public:
201 205

	
202 206
    SubMapExtender(const GraphType& _graph)
203 207
      : Parent(_graph), graph(_graph) {}
204 208

	
205 209
    SubMapExtender(const GraphType& _graph, const Value& _value)
206 210
      : Parent(_graph, _value), graph(_graph) {}
207 211

	
208 212
  private:
209 213
    SubMapExtender& operator=(const SubMapExtender& cmap) {
210 214
      return operator=<MapExtender>(cmap);
211 215
    }
212 216

	
213 217
    template <typename CMap>
214 218
    SubMapExtender& operator=(const CMap& cmap) {
215 219
      checkConcept<concepts::ReadMap<Key, Value>, CMap>();
216 220
      Item it;
217 221
      for (graph.first(it); it != INVALID; graph.next(it)) {
218 222
        Parent::set(it, cmap[it]);
219 223
      }
220 224
      return *this;
221 225
    }
222 226

	
223 227
  public:
224 228
    class MapIt : public Item {
225 229
      typedef Item Parent;
226 230

	
227 231
    public:
228 232
      typedef typename Map::Value Value;
229 233

	
230 234
      MapIt() {}
231 235

	
232 236
      MapIt(Invalid i) : Parent(i) { }
233 237

	
234 238
      explicit MapIt(Map& _map) : map(_map) {
235 239
        map.graph.first(*this);
236 240
      }
237 241

	
238 242
      MapIt(const Map& _map, const Item& item)
239 243
        : Parent(item), map(_map) {}
240 244

	
241 245
      MapIt& operator++() {
242 246
        map.graph.next(*this);
243 247
        return *this;
244 248
      }
245 249

	
246 250
      typename MapTraits<Map>::ConstReturnValue operator*() const {
247 251
        return map[*this];
248 252
      }
249 253

	
250 254
      typename MapTraits<Map>::ReturnValue operator*() {
251 255
        return map[*this];
252 256
      }
253 257

	
254 258
      void set(const Value& value) {
255 259
        map.set(*this, value);
256 260
      }
257 261

	
258 262
    protected:
259 263
      Map& map;
260 264

	
261 265
    };
262 266

	
263 267
    class ConstMapIt : public Item {
264 268
      typedef Item Parent;
265 269

	
266 270
    public:
267 271

	
268 272
      typedef typename Map::Value Value;
269 273

	
270 274
      ConstMapIt() {}
271 275

	
272 276
      ConstMapIt(Invalid i) : Parent(i) { }
273 277

	
274 278
      explicit ConstMapIt(Map& _map) : map(_map) {
275 279
        map.graph.first(*this);
276 280
      }
277 281

	
278 282
      ConstMapIt(const Map& _map, const Item& item)
279 283
        : Parent(item), map(_map) {}
280 284

	
281 285
      ConstMapIt& operator++() {
282 286
        map.graph.next(*this);
283 287
        return *this;
284 288
      }
285 289

	
286 290
      typename MapTraits<Map>::ConstReturnValue operator*() const {
287 291
        return map[*this];
288 292
      }
289 293

	
290 294
    protected:
291 295
      const Map& map;
292 296
    };
293 297

	
294 298
    class ItemIt : public Item {
295 299
      typedef Item Parent;
296 300

	
297 301
    public:
298 302

	
299 303
      ItemIt() {}
300 304

	
301 305
      ItemIt(Invalid i) : Parent(i) { }
302 306

	
303 307
      explicit ItemIt(Map& _map) : map(_map) {
304 308
        map.graph.first(*this);
305 309
      }
306 310

	
307 311
      ItemIt(const Map& _map, const Item& item)
308 312
        : Parent(item), map(_map) {}
309 313

	
310 314
      ItemIt& operator++() {
311 315
        map.graph.next(*this);
312 316
        return *this;
313 317
      }
314 318

	
315 319
    protected:
316 320
      const Map& map;
317 321

	
318 322
    };
319 323

	
320 324
  private:
321 325

	
322 326
    const GraphType& graph;
323 327

	
324 328
  };
325 329

	
326 330
}
327 331

	
328 332
#endif
Ignore white space 6 line context
1 1
/* -*- mode: C++; indent-tabs-mode: nil; -*-
2 2
 *
3 3
 * This file is a part of LEMON, a generic C++ optimization library.
4 4
 *
5 5
 * Copyright (C) 2003-2009
6 6
 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 7
 * (Egervary Research Group on Combinatorial Optimization, EGRES).
8 8
 *
9 9
 * Permission to use, modify and distribute this software is granted
10 10
 * provided that this copyright notice appears in all copies. For
11 11
 * precise terms see the accompanying LICENSE file.
12 12
 *
13 13
 * This software is provided "AS IS" with no warranty of any kind,
14 14
 * express or implied, and with no claim as to its suitability for any
15 15
 * purpose.
16 16
 *
17 17
 */
18 18

	
19 19
#ifndef LEMON_CIRCULATION_H
20 20
#define LEMON_CIRCULATION_H
21 21

	
22 22
#include <lemon/tolerance.h>
23 23
#include <lemon/elevator.h>
24 24
#include <limits>
25 25

	
26 26
///\ingroup max_flow
27 27
///\file
28 28
///\brief Push-relabel algorithm for finding a feasible circulation.
29 29
///
30 30
namespace lemon {
31 31

	
32 32
  /// \brief Default traits class of Circulation class.
33 33
  ///
34 34
  /// Default traits class of Circulation class.
35 35
  ///
36 36
  /// \tparam GR Type of the digraph the algorithm runs on.
37 37
  /// \tparam LM The type of the lower bound map.
38 38
  /// \tparam UM The type of the upper bound (capacity) map.
39 39
  /// \tparam SM The type of the supply map.
40 40
  template <typename GR, typename LM,
41 41
            typename UM, typename SM>
42 42
  struct CirculationDefaultTraits {
43 43

	
44 44
    /// \brief The type of the digraph the algorithm runs on.
45 45
    typedef GR Digraph;
46 46

	
47 47
    /// \brief The type of the lower bound map.
48 48
    ///
49 49
    /// The type of the map that stores the lower bounds on the arcs.
50 50
    /// It must conform to the \ref concepts::ReadMap "ReadMap" concept.
51 51
    typedef LM LowerMap;
52 52

	
53 53
    /// \brief The type of the upper bound (capacity) map.
54 54
    ///
55 55
    /// The type of the map that stores the upper bounds (capacities)
56 56
    /// on the arcs.
57 57
    /// It must conform to the \ref concepts::ReadMap "ReadMap" concept.
58 58
    typedef UM UpperMap;
59 59

	
60 60
    /// \brief The type of supply map.
61 61
    ///
62 62
    /// The type of the map that stores the signed supply values of the 
63 63
    /// nodes. 
64 64
    /// It must conform to the \ref concepts::ReadMap "ReadMap" concept.
65 65
    typedef SM SupplyMap;
66 66

	
67 67
    /// \brief The type of the flow and supply values.
68 68
    typedef typename SupplyMap::Value Value;
69 69

	
70 70
    /// \brief The type of the map that stores the flow values.
71 71
    ///
72 72
    /// The type of the map that stores the flow values.
73 73
    /// It must conform to the \ref concepts::ReadWriteMap "ReadWriteMap"
74 74
    /// concept.
75
#ifdef DOXYGEN
76
    typedef GR::ArcMap<Value> FlowMap;
77
#else
75 78
    typedef typename Digraph::template ArcMap<Value> FlowMap;
79
#endif
76 80

	
77 81
    /// \brief Instantiates a FlowMap.
78 82
    ///
79 83
    /// This function instantiates a \ref FlowMap.
80 84
    /// \param digraph The digraph for which we would like to define
81 85
    /// the flow map.
82 86
    static FlowMap* createFlowMap(const Digraph& digraph) {
83 87
      return new FlowMap(digraph);
84 88
    }
85 89

	
86 90
    /// \brief The elevator type used by the algorithm.
87 91
    ///
88 92
    /// The elevator type used by the algorithm.
89 93
    ///
90
    /// \sa Elevator
91
    /// \sa LinkedElevator
94
    /// \sa Elevator, LinkedElevator
95
#ifdef DOXYGEN
96
    typedef lemon::Elevator<GR, GR::Node> Elevator;
97
#else
92 98
    typedef lemon::Elevator<Digraph, typename Digraph::Node> Elevator;
99
#endif
93 100

	
94 101
    /// \brief Instantiates an Elevator.
95 102
    ///
96 103
    /// This function instantiates an \ref Elevator.
97 104
    /// \param digraph The digraph for which we would like to define
98 105
    /// the elevator.
99 106
    /// \param max_level The maximum level of the elevator.
100 107
    static Elevator* createElevator(const Digraph& digraph, int max_level) {
101 108
      return new Elevator(digraph, max_level);
102 109
    }
103 110

	
104 111
    /// \brief The tolerance used by the algorithm
105 112
    ///
106 113
    /// The tolerance used by the algorithm to handle inexact computation.
107 114
    typedef lemon::Tolerance<Value> Tolerance;
108 115

	
109 116
  };
110 117

	
111 118
  /**
112 119
     \brief Push-relabel algorithm for the network circulation problem.
113 120

	
114 121
     \ingroup max_flow
115 122
     This class implements a push-relabel algorithm for the \e network
116 123
     \e circulation problem.
117 124
     It is to find a feasible circulation when lower and upper bounds
118 125
     are given for the flow values on the arcs and lower bounds are
119 126
     given for the difference between the outgoing and incoming flow
120 127
     at the nodes.
121 128

	
122 129
     The exact formulation of this problem is the following.
123 130
     Let \f$G=(V,A)\f$ be a digraph, \f$lower: A\rightarrow\mathbf{R}\f$
124 131
     \f$upper: A\rightarrow\mathbf{R}\cup\{\infty\}\f$ denote the lower and
125 132
     upper bounds on the arcs, for which \f$lower(uv) \leq upper(uv)\f$
126 133
     holds for all \f$uv\in A\f$, and \f$sup: V\rightarrow\mathbf{R}\f$
127 134
     denotes the signed supply values of the nodes.
128 135
     If \f$sup(u)>0\f$, then \f$u\f$ is a supply node with \f$sup(u)\f$
129 136
     supply, if \f$sup(u)<0\f$, then \f$u\f$ is a demand node with
130 137
     \f$-sup(u)\f$ demand.
131 138
     A feasible circulation is an \f$f: A\rightarrow\mathbf{R}\f$
132 139
     solution of the following problem.
133 140

	
134 141
     \f[ \sum_{uv\in A} f(uv) - \sum_{vu\in A} f(vu)
135 142
     \geq sup(u) \quad \forall u\in V, \f]
136 143
     \f[ lower(uv) \leq f(uv) \leq upper(uv) \quad \forall uv\in A. \f]
137 144
     
138 145
     The sum of the supply values, i.e. \f$\sum_{u\in V} sup(u)\f$ must be
139 146
     zero or negative in order to have a feasible solution (since the sum
140 147
     of the expressions on the left-hand side of the inequalities is zero).
141 148
     It means that the total demand must be greater or equal to the total
142 149
     supply and all the supplies have to be carried out from the supply nodes,
143 150
     but there could be demands that are not satisfied.
144 151
     If \f$\sum_{u\in V} sup(u)\f$ is zero, then all the supply/demand
145 152
     constraints have to be satisfied with equality, i.e. all demands
146 153
     have to be satisfied and all supplies have to be used.
147 154
     
148 155
     If you need the opposite inequalities in the supply/demand constraints
149 156
     (i.e. the total demand is less than the total supply and all the demands
150 157
     have to be satisfied while there could be supplies that are not used),
151 158
     then you could easily transform the problem to the above form by reversing
152 159
     the direction of the arcs and taking the negative of the supply values
153 160
     (e.g. using \ref ReverseDigraph and \ref NegMap adaptors).
154 161

	
155 162
     This algorithm either calculates a feasible circulation, or provides
156 163
     a \ref barrier() "barrier", which prooves that a feasible soultion
157 164
     cannot exist.
158 165

	
159 166
     Note that this algorithm also provides a feasible solution for the
160 167
     \ref min_cost_flow "minimum cost flow problem".
161 168

	
162 169
     \tparam GR The type of the digraph the algorithm runs on.
163 170
     \tparam LM The type of the lower bound map. The default
164 171
     map type is \ref concepts::Digraph::ArcMap "GR::ArcMap<int>".
165 172
     \tparam UM The type of the upper bound (capacity) map.
166 173
     The default map type is \c LM.
167 174
     \tparam SM The type of the supply map. The default map type is
168 175
     \ref concepts::Digraph::NodeMap "GR::NodeMap<UM::Value>".
169 176
  */
170 177
#ifdef DOXYGEN
171 178
template< typename GR,
172 179
          typename LM,
173 180
          typename UM,
174 181
          typename SM,
175 182
          typename TR >
176 183
#else
177 184
template< typename GR,
178 185
          typename LM = typename GR::template ArcMap<int>,
179 186
          typename UM = LM,
180 187
          typename SM = typename GR::template NodeMap<typename UM::Value>,
181 188
          typename TR = CirculationDefaultTraits<GR, LM, UM, SM> >
182 189
#endif
183 190
  class Circulation {
184 191
  public:
185 192

	
186 193
    ///The \ref CirculationDefaultTraits "traits class" of the algorithm.
187 194
    typedef TR Traits;
188 195
    ///The type of the digraph the algorithm runs on.
189 196
    typedef typename Traits::Digraph Digraph;
190 197
    ///The type of the flow and supply values.
191 198
    typedef typename Traits::Value Value;
192 199

	
193 200
    ///The type of the lower bound map.
194 201
    typedef typename Traits::LowerMap LowerMap;
195 202
    ///The type of the upper bound (capacity) map.
196 203
    typedef typename Traits::UpperMap UpperMap;
197 204
    ///The type of the supply map.
198 205
    typedef typename Traits::SupplyMap SupplyMap;
199 206
    ///The type of the flow map.
200 207
    typedef typename Traits::FlowMap FlowMap;
201 208

	
202 209
    ///The type of the elevator.
203 210
    typedef typename Traits::Elevator Elevator;
204 211
    ///The type of the tolerance.
205 212
    typedef typename Traits::Tolerance Tolerance;
206 213

	
207 214
  private:
208 215

	
209 216
    TEMPLATE_DIGRAPH_TYPEDEFS(Digraph);
210 217

	
211 218
    const Digraph &_g;
212 219
    int _node_num;
213 220

	
214 221
    const LowerMap *_lo;
215 222
    const UpperMap *_up;
216 223
    const SupplyMap *_supply;
217 224

	
218 225
    FlowMap *_flow;
219 226
    bool _local_flow;
220 227

	
221 228
    Elevator* _level;
222 229
    bool _local_level;
223 230

	
224 231
    typedef typename Digraph::template NodeMap<Value> ExcessMap;
225 232
    ExcessMap* _excess;
226 233

	
227 234
    Tolerance _tol;
228 235
    int _el;
229 236

	
230 237
  public:
231 238

	
232 239
    typedef Circulation Create;
233 240

	
234 241
    ///\name Named Template Parameters
235 242

	
236 243
    ///@{
237 244

	
238 245
    template <typename T>
239 246
    struct SetFlowMapTraits : public Traits {
240 247
      typedef T FlowMap;
241 248
      static FlowMap *createFlowMap(const Digraph&) {
242 249
        LEMON_ASSERT(false, "FlowMap is not initialized");
243 250
        return 0; // ignore warnings
244 251
      }
245 252
    };
246 253

	
247 254
    /// \brief \ref named-templ-param "Named parameter" for setting
248 255
    /// FlowMap type
249 256
    ///
250 257
    /// \ref named-templ-param "Named parameter" for setting FlowMap
251 258
    /// type.
252 259
    template <typename T>
253 260
    struct SetFlowMap
254 261
      : public Circulation<Digraph, LowerMap, UpperMap, SupplyMap,
255 262
                           SetFlowMapTraits<T> > {
256 263
      typedef Circulation<Digraph, LowerMap, UpperMap, SupplyMap,
257 264
                          SetFlowMapTraits<T> > Create;
258 265
    };
259 266

	
260 267
    template <typename T>
261 268
    struct SetElevatorTraits : public Traits {
262 269
      typedef T Elevator;
263 270
      static Elevator *createElevator(const Digraph&, int) {
264 271
        LEMON_ASSERT(false, "Elevator is not initialized");
265 272
        return 0; // ignore warnings
266 273
      }
267 274
    };
268 275

	
269 276
    /// \brief \ref named-templ-param "Named parameter" for setting
270 277
    /// Elevator type
271 278
    ///
272 279
    /// \ref named-templ-param "Named parameter" for setting Elevator
273 280
    /// type. If this named parameter is used, then an external
274 281
    /// elevator object must be passed to the algorithm using the
275 282
    /// \ref elevator(Elevator&) "elevator()" function before calling
276 283
    /// \ref run() or \ref init().
277 284
    /// \sa SetStandardElevator
278 285
    template <typename T>
279 286
    struct SetElevator
280 287
      : public Circulation<Digraph, LowerMap, UpperMap, SupplyMap,
281 288
                           SetElevatorTraits<T> > {
282 289
      typedef Circulation<Digraph, LowerMap, UpperMap, SupplyMap,
283 290
                          SetElevatorTraits<T> > Create;
284 291
    };
285 292

	
286 293
    template <typename T>
287 294
    struct SetStandardElevatorTraits : public Traits {
288 295
      typedef T Elevator;
289 296
      static Elevator *createElevator(const Digraph& digraph, int max_level) {
290 297
        return new Elevator(digraph, max_level);
291 298
      }
292 299
    };
293 300

	
294 301
    /// \brief \ref named-templ-param "Named parameter" for setting
295 302
    /// Elevator type with automatic allocation
296 303
    ///
297 304
    /// \ref named-templ-param "Named parameter" for setting Elevator
298 305
    /// type with automatic allocation.
299 306
    /// The Elevator should have standard constructor interface to be
300 307
    /// able to automatically created by the algorithm (i.e. the
301 308
    /// digraph and the maximum level should be passed to it).
302 309
    /// However an external elevator object could also be passed to the
303 310
    /// algorithm with the \ref elevator(Elevator&) "elevator()" function
304 311
    /// before calling \ref run() or \ref init().
305 312
    /// \sa SetElevator
306 313
    template <typename T>
307 314
    struct SetStandardElevator
308 315
      : public Circulation<Digraph, LowerMap, UpperMap, SupplyMap,
309 316
                       SetStandardElevatorTraits<T> > {
310 317
      typedef Circulation<Digraph, LowerMap, UpperMap, SupplyMap,
311 318
                      SetStandardElevatorTraits<T> > Create;
312 319
    };
313 320

	
314 321
    /// @}
315 322

	
316 323
  protected:
317 324

	
318 325
    Circulation() {}
319 326

	
320 327
  public:
321 328

	
322 329
    /// Constructor.
323 330

	
324 331
    /// The constructor of the class.
325 332
    ///
326 333
    /// \param graph The digraph the algorithm runs on.
327 334
    /// \param lower The lower bounds for the flow values on the arcs.
328 335
    /// \param upper The upper bounds (capacities) for the flow values 
329 336
    /// on the arcs.
330 337
    /// \param supply The signed supply values of the nodes.
331 338
    Circulation(const Digraph &graph, const LowerMap &lower,
332 339
                const UpperMap &upper, const SupplyMap &supply)
333 340
      : _g(graph), _lo(&lower), _up(&upper), _supply(&supply),
334 341
        _flow(NULL), _local_flow(false), _level(NULL), _local_level(false),
335 342
        _excess(NULL) {}
336 343

	
337 344
    /// Destructor.
338 345
    ~Circulation() {
339 346
      destroyStructures();
340 347
    }
341 348

	
342 349

	
343 350
  private:
344 351

	
345 352
    bool checkBoundMaps() {
346 353
      for (ArcIt e(_g);e!=INVALID;++e) {
347 354
        if (_tol.less((*_up)[e], (*_lo)[e])) return false;
348 355
      }
349 356
      return true;
350 357
    }
351 358

	
352 359
    void createStructures() {
353 360
      _node_num = _el = countNodes(_g);
354 361

	
355 362
      if (!_flow) {
356 363
        _flow = Traits::createFlowMap(_g);
357 364
        _local_flow = true;
358 365
      }
359 366
      if (!_level) {
360 367
        _level = Traits::createElevator(_g, _node_num);
361 368
        _local_level = true;
362 369
      }
363 370
      if (!_excess) {
364 371
        _excess = new ExcessMap(_g);
365 372
      }
366 373
    }
367 374

	
368 375
    void destroyStructures() {
369 376
      if (_local_flow) {
370 377
        delete _flow;
371 378
      }
372 379
      if (_local_level) {
373 380
        delete _level;
374 381
      }
375 382
      if (_excess) {
376 383
        delete _excess;
377 384
      }
378 385
    }
379 386

	
380 387
  public:
381 388

	
382 389
    /// Sets the lower bound map.
383 390

	
384 391
    /// Sets the lower bound map.
385 392
    /// \return <tt>(*this)</tt>
386 393
    Circulation& lowerMap(const LowerMap& map) {
387 394
      _lo = &map;
388 395
      return *this;
389 396
    }
390 397

	
391 398
    /// Sets the upper bound (capacity) map.
392 399

	
393 400
    /// Sets the upper bound (capacity) map.
394 401
    /// \return <tt>(*this)</tt>
395 402
    Circulation& upperMap(const UpperMap& map) {
396 403
      _up = &map;
397 404
      return *this;
398 405
    }
399 406

	
400 407
    /// Sets the supply map.
401 408

	
402 409
    /// Sets the supply map.
403 410
    /// \return <tt>(*this)</tt>
404 411
    Circulation& supplyMap(const SupplyMap& map) {
405 412
      _supply = &map;
406 413
      return *this;
407 414
    }
408 415

	
409 416
    /// \brief Sets the flow map.
410 417
    ///
411 418
    /// Sets the flow map.
412 419
    /// If you don't use this function before calling \ref run() or
413 420
    /// \ref init(), an instance will be allocated automatically.
414 421
    /// The destructor deallocates this automatically allocated map,
415 422
    /// of course.
416 423
    /// \return <tt>(*this)</tt>
417 424
    Circulation& flowMap(FlowMap& map) {
418 425
      if (_local_flow) {
419 426
        delete _flow;
420 427
        _local_flow = false;
421 428
      }
422 429
      _flow = &map;
423 430
      return *this;
424 431
    }
425 432

	
426 433
    /// \brief Sets the elevator used by algorithm.
427 434
    ///
428 435
    /// Sets the elevator used by algorithm.
429 436
    /// If you don't use this function before calling \ref run() or
430 437
    /// \ref init(), an instance will be allocated automatically.
431 438
    /// The destructor deallocates this automatically allocated elevator,
432 439
    /// of course.
433 440
    /// \return <tt>(*this)</tt>
434 441
    Circulation& elevator(Elevator& elevator) {
435 442
      if (_local_level) {
436 443
        delete _level;
437 444
        _local_level = false;
438 445
      }
439 446
      _level = &elevator;
440 447
      return *this;
441 448
    }
442 449

	
443 450
    /// \brief Returns a const reference to the elevator.
444 451
    ///
445 452
    /// Returns a const reference to the elevator.
446 453
    ///
447 454
    /// \pre Either \ref run() or \ref init() must be called before
448 455
    /// using this function.
449 456
    const Elevator& elevator() const {
450 457
      return *_level;
451 458
    }
452 459

	
453 460
    /// \brief Sets the tolerance used by the algorithm.
454 461
    ///
455 462
    /// Sets the tolerance object used by the algorithm.
456 463
    /// \return <tt>(*this)</tt>
457 464
    Circulation& tolerance(const Tolerance& tolerance) {
458 465
      _tol = tolerance;
459 466
      return *this;
460 467
    }
461 468

	
462 469
    /// \brief Returns a const reference to the tolerance.
463 470
    ///
464 471
    /// Returns a const reference to the tolerance object used by
465 472
    /// the algorithm.
466 473
    const Tolerance& tolerance() const {
467 474
      return _tol;
468 475
    }
469 476

	
470 477
    /// \name Execution Control
471 478
    /// The simplest way to execute the algorithm is to call \ref run().\n
472
    /// If you need more control on the initial solution or the execution,
473
    /// first you have to call one of the \ref init() functions, then
479
    /// If you need better control on the initial solution or the execution,
480
    /// you have to call one of the \ref init() functions first, then
474 481
    /// the \ref start() function.
475 482

	
476 483
    ///@{
477 484

	
478 485
    /// Initializes the internal data structures.
479 486

	
480 487
    /// Initializes the internal data structures and sets all flow values
481 488
    /// to the lower bound.
482 489
    void init()
483 490
    {
484 491
      LEMON_DEBUG(checkBoundMaps(),
485 492
        "Upper bounds must be greater or equal to the lower bounds");
486 493

	
487 494
      createStructures();
488 495

	
489 496
      for(NodeIt n(_g);n!=INVALID;++n) {
490 497
        (*_excess)[n] = (*_supply)[n];
491 498
      }
492 499

	
493 500
      for (ArcIt e(_g);e!=INVALID;++e) {
494 501
        _flow->set(e, (*_lo)[e]);
495 502
        (*_excess)[_g.target(e)] += (*_flow)[e];
496 503
        (*_excess)[_g.source(e)] -= (*_flow)[e];
497 504
      }
498 505

	
499 506
      // global relabeling tested, but in general case it provides
500 507
      // worse performance for random digraphs
501 508
      _level->initStart();
502 509
      for(NodeIt n(_g);n!=INVALID;++n)
503 510
        _level->initAddItem(n);
504 511
      _level->initFinish();
505 512
      for(NodeIt n(_g);n!=INVALID;++n)
506 513
        if(_tol.positive((*_excess)[n]))
507 514
          _level->activate(n);
508 515
    }
509 516

	
510 517
    /// Initializes the internal data structures using a greedy approach.
511 518

	
512 519
    /// Initializes the internal data structures using a greedy approach
513 520
    /// to construct the initial solution.
514 521
    void greedyInit()
515 522
    {
516 523
      LEMON_DEBUG(checkBoundMaps(),
517 524
        "Upper bounds must be greater or equal to the lower bounds");
518 525

	
519 526
      createStructures();
520 527

	
521 528
      for(NodeIt n(_g);n!=INVALID;++n) {
522 529
        (*_excess)[n] = (*_supply)[n];
523 530
      }
524 531

	
525 532
      for (ArcIt e(_g);e!=INVALID;++e) {
526 533
        if (!_tol.less(-(*_excess)[_g.target(e)], (*_up)[e])) {
527 534
          _flow->set(e, (*_up)[e]);
528 535
          (*_excess)[_g.target(e)] += (*_up)[e];
529 536
          (*_excess)[_g.source(e)] -= (*_up)[e];
530 537
        } else if (_tol.less(-(*_excess)[_g.target(e)], (*_lo)[e])) {
531 538
          _flow->set(e, (*_lo)[e]);
532 539
          (*_excess)[_g.target(e)] += (*_lo)[e];
533 540
          (*_excess)[_g.source(e)] -= (*_lo)[e];
534 541
        } else {
535 542
          Value fc = -(*_excess)[_g.target(e)];
536 543
          _flow->set(e, fc);
537 544
          (*_excess)[_g.target(e)] = 0;
538 545
          (*_excess)[_g.source(e)] -= fc;
539 546
        }
540 547
      }
541 548

	
542 549
      _level->initStart();
543 550
      for(NodeIt n(_g);n!=INVALID;++n)
544 551
        _level->initAddItem(n);
545 552
      _level->initFinish();
546 553
      for(NodeIt n(_g);n!=INVALID;++n)
547 554
        if(_tol.positive((*_excess)[n]))
548 555
          _level->activate(n);
549 556
    }
550 557

	
551 558
    ///Executes the algorithm
552 559

	
553 560
    ///This function executes the algorithm.
554 561
    ///
555 562
    ///\return \c true if a feasible circulation is found.
556 563
    ///
557 564
    ///\sa barrier()
558 565
    ///\sa barrierMap()
559 566
    bool start()
560 567
    {
561 568

	
562 569
      Node act;
563 570
      Node bact=INVALID;
564 571
      Node last_activated=INVALID;
565 572
      while((act=_level->highestActive())!=INVALID) {
566 573
        int actlevel=(*_level)[act];
567 574
        int mlevel=_node_num;
568 575
        Value exc=(*_excess)[act];
569 576

	
570 577
        for(OutArcIt e(_g,act);e!=INVALID; ++e) {
571 578
          Node v = _g.target(e);
572 579
          Value fc=(*_up)[e]-(*_flow)[e];
573 580
          if(!_tol.positive(fc)) continue;
574 581
          if((*_level)[v]<actlevel) {
575 582
            if(!_tol.less(fc, exc)) {
576 583
              _flow->set(e, (*_flow)[e] + exc);
577 584
              (*_excess)[v] += exc;
578 585
              if(!_level->active(v) && _tol.positive((*_excess)[v]))
579 586
                _level->activate(v);
580 587
              (*_excess)[act] = 0;
581 588
              _level->deactivate(act);
582 589
              goto next_l;
583 590
            }
584 591
            else {
585 592
              _flow->set(e, (*_up)[e]);
586 593
              (*_excess)[v] += fc;
587 594
              if(!_level->active(v) && _tol.positive((*_excess)[v]))
588 595
                _level->activate(v);
589 596
              exc-=fc;
590 597
            }
591 598
          }
592 599
          else if((*_level)[v]<mlevel) mlevel=(*_level)[v];
593 600
        }
594 601
        for(InArcIt e(_g,act);e!=INVALID; ++e) {
595 602
          Node v = _g.source(e);
596 603
          Value fc=(*_flow)[e]-(*_lo)[e];
597 604
          if(!_tol.positive(fc)) continue;
598 605
          if((*_level)[v]<actlevel) {
599 606
            if(!_tol.less(fc, exc)) {
600 607
              _flow->set(e, (*_flow)[e] - exc);
601 608
              (*_excess)[v] += exc;
602 609
              if(!_level->active(v) && _tol.positive((*_excess)[v]))
603 610
                _level->activate(v);
604 611
              (*_excess)[act] = 0;
605 612
              _level->deactivate(act);
606 613
              goto next_l;
607 614
            }
608 615
            else {
609 616
              _flow->set(e, (*_lo)[e]);
610 617
              (*_excess)[v] += fc;
611 618
              if(!_level->active(v) && _tol.positive((*_excess)[v]))
612 619
                _level->activate(v);
613 620
              exc-=fc;
614 621
            }
615 622
          }
616 623
          else if((*_level)[v]<mlevel) mlevel=(*_level)[v];
617 624
        }
618 625

	
619 626
        (*_excess)[act] = exc;
620 627
        if(!_tol.positive(exc)) _level->deactivate(act);
621 628
        else if(mlevel==_node_num) {
622 629
          _level->liftHighestActiveToTop();
623 630
          _el = _node_num;
624 631
          return false;
625 632
        }
626 633
        else {
627 634
          _level->liftHighestActive(mlevel+1);
628 635
          if(_level->onLevel(actlevel)==0) {
629 636
            _el = actlevel;
630 637
            return false;
631 638
          }
632 639
        }
633 640
      next_l:
634 641
        ;
635 642
      }
636 643
      return true;
637 644
    }
638 645

	
639 646
    /// Runs the algorithm.
640 647

	
641 648
    /// This function runs the algorithm.
642 649
    ///
643 650
    /// \return \c true if a feasible circulation is found.
644 651
    ///
645 652
    /// \note Apart from the return value, c.run() is just a shortcut of
646 653
    /// the following code.
647 654
    /// \code
648 655
    ///   c.greedyInit();
649 656
    ///   c.start();
650 657
    /// \endcode
651 658
    bool run() {
652 659
      greedyInit();
653 660
      return start();
654 661
    }
655 662

	
656 663
    /// @}
657 664

	
658 665
    /// \name Query Functions
659 666
    /// The results of the circulation algorithm can be obtained using
660 667
    /// these functions.\n
661 668
    /// Either \ref run() or \ref start() should be called before
662 669
    /// using them.
663 670

	
664 671
    ///@{
665 672

	
666 673
    /// \brief Returns the flow value on the given arc.
667 674
    ///
668 675
    /// Returns the flow value on the given arc.
669 676
    ///
670 677
    /// \pre Either \ref run() or \ref init() must be called before
671 678
    /// using this function.
672 679
    Value flow(const Arc& arc) const {
673 680
      return (*_flow)[arc];
674 681
    }
675 682

	
676 683
    /// \brief Returns a const reference to the flow map.
677 684
    ///
678 685
    /// Returns a const reference to the arc map storing the found flow.
679 686
    ///
680 687
    /// \pre Either \ref run() or \ref init() must be called before
681 688
    /// using this function.
682 689
    const FlowMap& flowMap() const {
683 690
      return *_flow;
684 691
    }
685 692

	
686 693
    /**
687 694
       \brief Returns \c true if the given node is in a barrier.
688 695

	
689 696
       Barrier is a set \e B of nodes for which
690 697

	
691 698
       \f[ \sum_{uv\in A: u\in B} upper(uv) -
692 699
           \sum_{uv\in A: v\in B} lower(uv) < \sum_{v\in B} sup(v) \f]
693 700

	
694 701
       holds. The existence of a set with this property prooves that a
695 702
       feasible circualtion cannot exist.
696 703

	
697 704
       This function returns \c true if the given node is in the found
698 705
       barrier. If a feasible circulation is found, the function
699 706
       gives back \c false for every node.
700 707

	
701 708
       \pre Either \ref run() or \ref init() must be called before
702 709
       using this function.
703 710

	
704 711
       \sa barrierMap()
705 712
       \sa checkBarrier()
706 713
    */
707 714
    bool barrier(const Node& node) const
708 715
    {
709 716
      return (*_level)[node] >= _el;
710 717
    }
711 718

	
712 719
    /// \brief Gives back a barrier.
713 720
    ///
714 721
    /// This function sets \c bar to the characteristic vector of the
715 722
    /// found barrier. \c bar should be a \ref concepts::WriteMap "writable"
716 723
    /// node map with \c bool (or convertible) value type.
717 724
    ///
718 725
    /// If a feasible circulation is found, the function gives back an
719 726
    /// empty set, so \c bar[v] will be \c false for all nodes \c v.
720 727
    ///
721 728
    /// \note This function calls \ref barrier() for each node,
722 729
    /// so it runs in O(n) time.
723 730
    ///
724 731
    /// \pre Either \ref run() or \ref init() must be called before
725 732
    /// using this function.
726 733
    ///
727 734
    /// \sa barrier()
728 735
    /// \sa checkBarrier()
729 736
    template<class BarrierMap>
730 737
    void barrierMap(BarrierMap &bar) const
731 738
    {
732 739
      for(NodeIt n(_g);n!=INVALID;++n)
733 740
        bar.set(n, (*_level)[n] >= _el);
734 741
    }
735 742

	
736 743
    /// @}
737 744

	
738 745
    /// \name Checker Functions
739 746
    /// The feasibility of the results can be checked using
740 747
    /// these functions.\n
741 748
    /// Either \ref run() or \ref start() should be called before
742 749
    /// using them.
743 750

	
744 751
    ///@{
745 752

	
746 753
    ///Check if the found flow is a feasible circulation
747 754

	
748 755
    ///Check if the found flow is a feasible circulation,
749 756
    ///
750 757
    bool checkFlow() const {
751 758
      for(ArcIt e(_g);e!=INVALID;++e)
752 759
        if((*_flow)[e]<(*_lo)[e]||(*_flow)[e]>(*_up)[e]) return false;
753 760
      for(NodeIt n(_g);n!=INVALID;++n)
754 761
        {
755 762
          Value dif=-(*_supply)[n];
756 763
          for(InArcIt e(_g,n);e!=INVALID;++e) dif-=(*_flow)[e];
757 764
          for(OutArcIt e(_g,n);e!=INVALID;++e) dif+=(*_flow)[e];
758 765
          if(_tol.negative(dif)) return false;
759 766
        }
760 767
      return true;
761 768
    }
762 769

	
763 770
    ///Check whether or not the last execution provides a barrier
764 771

	
765 772
    ///Check whether or not the last execution provides a barrier.
766 773
    ///\sa barrier()
767 774
    ///\sa barrierMap()
768 775
    bool checkBarrier() const
769 776
    {
770 777
      Value delta=0;
771 778
      Value inf_cap = std::numeric_limits<Value>::has_infinity ?
772 779
        std::numeric_limits<Value>::infinity() :
773 780
        std::numeric_limits<Value>::max();
774 781
      for(NodeIt n(_g);n!=INVALID;++n)
775 782
        if(barrier(n))
776 783
          delta-=(*_supply)[n];
777 784
      for(ArcIt e(_g);e!=INVALID;++e)
778 785
        {
779 786
          Node s=_g.source(e);
780 787
          Node t=_g.target(e);
781 788
          if(barrier(s)&&!barrier(t)) {
782 789
            if (_tol.less(inf_cap - (*_up)[e], delta)) return false;
783 790
            delta+=(*_up)[e];
784 791
          }
785 792
          else if(barrier(t)&&!barrier(s)) delta-=(*_lo)[e];
786 793
        }
787 794
      return _tol.negative(delta);
788 795
    }
789 796

	
790 797
    /// @}
791 798

	
792 799
  };
793 800

	
794 801
}
795 802

	
796 803
#endif
Ignore white space 6 line context
1 1
/* -*- mode: C++; indent-tabs-mode: nil; -*-
2 2
 *
3 3
 * This file is a part of LEMON, a generic C++ optimization library.
4 4
 *
5 5
 * Copyright (C) 2003-2009
6 6
 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 7
 * (Egervary Research Group on Combinatorial Optimization, EGRES).
8 8
 *
9 9
 * Permission to use, modify and distribute this software is granted
10 10
 * provided that this copyright notice appears in all copies. For
11 11
 * precise terms see the accompanying LICENSE file.
12 12
 *
13 13
 * This software is provided "AS IS" with no warranty of any kind,
14 14
 * express or implied, and with no claim as to its suitability for any
15 15
 * purpose.
16 16
 *
17 17
 */
18 18

	
19 19
#ifndef LEMON_CONCEPTS_MAPS_H
20 20
#define LEMON_CONCEPTS_MAPS_H
21 21

	
22 22
#include <lemon/core.h>
23 23
#include <lemon/concept_check.h>
24 24

	
25 25
///\ingroup map_concepts
26 26
///\file
27 27
///\brief The concept of maps.
28 28

	
29 29
namespace lemon {
30 30

	
31 31
  namespace concepts {
32 32

	
33 33
    /// \addtogroup map_concepts
34 34
    /// @{
35 35

	
36 36
    /// Readable map concept
37 37

	
38 38
    /// Readable map concept.
39 39
    ///
40 40
    template<typename K, typename T>
41 41
    class ReadMap
42 42
    {
43 43
    public:
44 44
      /// The key type of the map.
45 45
      typedef K Key;
46 46
      /// \brief The value type of the map.
47 47
      /// (The type of objects associated with the keys).
48 48
      typedef T Value;
49 49

	
50 50
      /// Returns the value associated with the given key.
51 51
      Value operator[](const Key &) const {
52 52
        return *static_cast<Value *>(0);
53 53
      }
54 54

	
55 55
      template<typename _ReadMap>
56 56
      struct Constraints {
57 57
        void constraints() {
58 58
          Value val = m[key];
59 59
          val = m[key];
60 60
          typename _ReadMap::Value own_val = m[own_key];
61 61
          own_val = m[own_key];
62 62

	
63 63
          ignore_unused_variable_warning(key);
64 64
          ignore_unused_variable_warning(val);
65 65
          ignore_unused_variable_warning(own_key);
66 66
          ignore_unused_variable_warning(own_val);
67 67
        }
68 68
        const Key& key;
69 69
        const typename _ReadMap::Key& own_key;
70 70
        const _ReadMap& m;
71 71
      };
72 72

	
73 73
    };
74 74

	
75 75

	
76 76
    /// Writable map concept
77 77

	
78 78
    /// Writable map concept.
79 79
    ///
80 80
    template<typename K, typename T>
81 81
    class WriteMap
82 82
    {
83 83
    public:
84 84
      /// The key type of the map.
85 85
      typedef K Key;
86 86
      /// \brief The value type of the map.
87 87
      /// (The type of objects associated with the keys).
88 88
      typedef T Value;
89 89

	
90 90
      /// Sets the value associated with the given key.
91 91
      void set(const Key &, const Value &) {}
92 92

	
93 93
      /// Default constructor.
94 94
      WriteMap() {}
95 95

	
96 96
      template <typename _WriteMap>
97 97
      struct Constraints {
98 98
        void constraints() {
99 99
          m.set(key, val);
100 100
          m.set(own_key, own_val);
101 101

	
102 102
          ignore_unused_variable_warning(key);
103 103
          ignore_unused_variable_warning(val);
104 104
          ignore_unused_variable_warning(own_key);
105 105
          ignore_unused_variable_warning(own_val);
106 106
        }
107 107
        const Key& key;
108 108
        const Value& val;
109 109
        const typename _WriteMap::Key& own_key;
110 110
        const typename _WriteMap::Value& own_val;
111 111
        _WriteMap& m;
112 112
      };
113 113
    };
114 114

	
115 115
    /// Read/writable map concept
116 116

	
117 117
    /// Read/writable map concept.
118 118
    ///
119 119
    template<typename K, typename T>
120 120
    class ReadWriteMap : public ReadMap<K,T>,
121 121
                         public WriteMap<K,T>
122 122
    {
123 123
    public:
124 124
      /// The key type of the map.
125 125
      typedef K Key;
126 126
      /// \brief The value type of the map.
127 127
      /// (The type of objects associated with the keys).
128 128
      typedef T Value;
129 129

	
130 130
      /// Returns the value associated with the given key.
131 131
      Value operator[](const Key &) const {
132 132
        return *static_cast<Value *>(0);
133 133
      }
134 134

	
135 135
      /// Sets the value associated with the given key.
136 136
      void set(const Key &, const Value &) {}
137 137

	
138 138
      template<typename _ReadWriteMap>
139 139
      struct Constraints {
140 140
        void constraints() {
141 141
          checkConcept<ReadMap<K, T>, _ReadWriteMap >();
142 142
          checkConcept<WriteMap<K, T>, _ReadWriteMap >();
143 143
        }
144 144
      };
145 145
    };
146 146

	
147 147

	
148 148
    /// Dereferable map concept
149 149

	
150 150
    /// Dereferable map concept.
151 151
    ///
152 152
    template<typename K, typename T, typename R, typename CR>
153 153
    class ReferenceMap : public ReadWriteMap<K,T>
154 154
    {
155 155
    public:
156 156
      /// Tag for reference maps.
157 157
      typedef True ReferenceMapTag;
158 158
      /// The key type of the map.
159 159
      typedef K Key;
160 160
      /// \brief The value type of the map.
161 161
      /// (The type of objects associated with the keys).
162 162
      typedef T Value;
163 163
      /// The reference type of the map.
164 164
      typedef R Reference;
165 165
      /// The const reference type of the map.
166 166
      typedef CR ConstReference;
167 167

	
168 168
    public:
169 169

	
170 170
      /// Returns a reference to the value associated with the given key.
171 171
      Reference operator[](const Key &) {
172 172
        return *static_cast<Value *>(0);
173 173
      }
174 174

	
175 175
      /// Returns a const reference to the value associated with the given key.
176 176
      ConstReference operator[](const Key &) const {
177 177
        return *static_cast<Value *>(0);
178 178
      }
179 179

	
180 180
      /// Sets the value associated with the given key.
181 181
      void set(const Key &k,const Value &t) { operator[](k)=t; }
182 182

	
183 183
      template<typename _ReferenceMap>
184 184
      struct Constraints {
185
        void constraints() {
185
        typename enable_if<typename _ReferenceMap::ReferenceMapTag, void>::type
186
        constraints() {
186 187
          checkConcept<ReadWriteMap<K, T>, _ReferenceMap >();
187 188
          ref = m[key];
188 189
          m[key] = val;
189 190
          m[key] = ref;
190 191
          m[key] = cref;
191 192
          own_ref = m[own_key];
192 193
          m[own_key] = own_val;
193 194
          m[own_key] = own_ref;
194 195
          m[own_key] = own_cref;
195 196
          m[key] = m[own_key];
196 197
          m[own_key] = m[key];
197 198
        }
198 199
        const Key& key;
199 200
        Value& val;
200 201
        Reference ref;
201 202
        ConstReference cref;
202 203
        const typename _ReferenceMap::Key& own_key;
203 204
        typename _ReferenceMap::Value& own_val;
204 205
        typename _ReferenceMap::Reference own_ref;
205 206
        typename _ReferenceMap::ConstReference own_cref;
206 207
        _ReferenceMap& m;
207 208
      };
208 209
    };
209 210

	
210 211
    // @}
211 212

	
212 213
  } //namespace concepts
213 214

	
214 215
} //namespace lemon
215 216

	
216 217
#endif
Ignore white space 6 line context
1 1
/* -*- mode: C++; indent-tabs-mode: nil; -*-
2 2
 *
3 3
 * This file is a part of LEMON, a generic C++ optimization library.
4 4
 *
5 5
 * Copyright (C) 2003-2009
6 6
 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 7
 * (Egervary Research Group on Combinatorial Optimization, EGRES).
8 8
 *
9 9
 * Permission to use, modify and distribute this software is granted
10 10
 * provided that this copyright notice appears in all copies. For
11 11
 * precise terms see the accompanying LICENSE file.
12 12
 *
13 13
 * This software is provided "AS IS" with no warranty of any kind,
14 14
 * express or implied, and with no claim as to its suitability for any
15 15
 * purpose.
16 16
 *
17 17
 */
18 18

	
19 19
#ifndef LEMON_DFS_H
20 20
#define LEMON_DFS_H
21 21

	
22 22
///\ingroup search
23 23
///\file
24 24
///\brief DFS algorithm.
25 25

	
26 26
#include <lemon/list_graph.h>
27 27
#include <lemon/bits/path_dump.h>
28 28
#include <lemon/core.h>
29 29
#include <lemon/error.h>
30 30
#include <lemon/maps.h>
31 31
#include <lemon/path.h>
32 32

	
33 33
namespace lemon {
34 34

	
35 35
  ///Default traits class of Dfs class.
36 36

	
37 37
  ///Default traits class of Dfs class.
38 38
  ///\tparam GR Digraph type.
39 39
  template<class GR>
40 40
  struct DfsDefaultTraits
41 41
  {
42 42
    ///The type of the digraph the algorithm runs on.
43 43
    typedef GR Digraph;
44 44

	
45 45
    ///\brief The type of the map that stores the predecessor
46 46
    ///arcs of the %DFS paths.
47 47
    ///
48 48
    ///The type of the map that stores the predecessor
49 49
    ///arcs of the %DFS paths.
50
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
50
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
51 51
    typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap;
52 52
    ///Instantiates a \c PredMap.
53 53

	
54 54
    ///This function instantiates a \ref PredMap.
55 55
    ///\param g is the digraph, to which we would like to define the
56 56
    ///\ref PredMap.
57 57
    static PredMap *createPredMap(const Digraph &g)
58 58
    {
59 59
      return new PredMap(g);
60 60
    }
61 61

	
62 62
    ///The type of the map that indicates which nodes are processed.
63 63

	
64 64
    ///The type of the map that indicates which nodes are processed.
65
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
65
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
66
    ///By default it is a NullMap.
66 67
    typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
67 68
    ///Instantiates a \c ProcessedMap.
68 69

	
69 70
    ///This function instantiates a \ref ProcessedMap.
70 71
    ///\param g is the digraph, to which
71 72
    ///we would like to define the \ref ProcessedMap.
72 73
#ifdef DOXYGEN
73 74
    static ProcessedMap *createProcessedMap(const Digraph &g)
74 75
#else
75 76
    static ProcessedMap *createProcessedMap(const Digraph &)
76 77
#endif
77 78
    {
78 79
      return new ProcessedMap();
79 80
    }
80 81

	
81 82
    ///The type of the map that indicates which nodes are reached.
82 83

	
83 84
    ///The type of the map that indicates which nodes are reached.
84
    ///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
85
    ///It must conform to the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
85 86
    typedef typename Digraph::template NodeMap<bool> ReachedMap;
86 87
    ///Instantiates a \c ReachedMap.
87 88

	
88 89
    ///This function instantiates a \ref ReachedMap.
89 90
    ///\param g is the digraph, to which
90 91
    ///we would like to define the \ref ReachedMap.
91 92
    static ReachedMap *createReachedMap(const Digraph &g)
92 93
    {
93 94
      return new ReachedMap(g);
94 95
    }
95 96

	
96 97
    ///The type of the map that stores the distances of the nodes.
97 98

	
98 99
    ///The type of the map that stores the distances of the nodes.
99
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
100
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
100 101
    typedef typename Digraph::template NodeMap<int> DistMap;
101 102
    ///Instantiates a \c DistMap.
102 103

	
103 104
    ///This function instantiates a \ref DistMap.
104 105
    ///\param g is the digraph, to which we would like to define the
105 106
    ///\ref DistMap.
106 107
    static DistMap *createDistMap(const Digraph &g)
107 108
    {
108 109
      return new DistMap(g);
109 110
    }
110 111
  };
111 112

	
112 113
  ///%DFS algorithm class.
113 114

	
114 115
  ///\ingroup search
115 116
  ///This class provides an efficient implementation of the %DFS algorithm.
116 117
  ///
117 118
  ///There is also a \ref dfs() "function-type interface" for the DFS
118 119
  ///algorithm, which is convenient in the simplier cases and it can be
119 120
  ///used easier.
120 121
  ///
121 122
  ///\tparam GR The type of the digraph the algorithm runs on.
122 123
  ///The default type is \ref ListDigraph.
123 124
#ifdef DOXYGEN
124 125
  template <typename GR,
125 126
            typename TR>
126 127
#else
127 128
  template <typename GR=ListDigraph,
128 129
            typename TR=DfsDefaultTraits<GR> >
129 130
#endif
130 131
  class Dfs {
131 132
  public:
132 133

	
133 134
    ///The type of the digraph the algorithm runs on.
134 135
    typedef typename TR::Digraph Digraph;
135 136

	
136 137
    ///\brief The type of the map that stores the predecessor arcs of the
137 138
    ///DFS paths.
138 139
    typedef typename TR::PredMap PredMap;
139 140
    ///The type of the map that stores the distances of the nodes.
140 141
    typedef typename TR::DistMap DistMap;
141 142
    ///The type of the map that indicates which nodes are reached.
142 143
    typedef typename TR::ReachedMap ReachedMap;
143 144
    ///The type of the map that indicates which nodes are processed.
144 145
    typedef typename TR::ProcessedMap ProcessedMap;
145 146
    ///The type of the paths.
146 147
    typedef PredMapPath<Digraph, PredMap> Path;
147 148

	
148 149
    ///The \ref DfsDefaultTraits "traits class" of the algorithm.
149 150
    typedef TR Traits;
150 151

	
151 152
  private:
152 153

	
153 154
    typedef typename Digraph::Node Node;
154 155
    typedef typename Digraph::NodeIt NodeIt;
155 156
    typedef typename Digraph::Arc Arc;
156 157
    typedef typename Digraph::OutArcIt OutArcIt;
157 158

	
158 159
    //Pointer to the underlying digraph.
159 160
    const Digraph *G;
160 161
    //Pointer to the map of predecessor arcs.
161 162
    PredMap *_pred;
162 163
    //Indicates if _pred is locally allocated (true) or not.
163 164
    bool local_pred;
164 165
    //Pointer to the map of distances.
165 166
    DistMap *_dist;
166 167
    //Indicates if _dist is locally allocated (true) or not.
167 168
    bool local_dist;
168 169
    //Pointer to the map of reached status of the nodes.
169 170
    ReachedMap *_reached;
170 171
    //Indicates if _reached is locally allocated (true) or not.
171 172
    bool local_reached;
172 173
    //Pointer to the map of processed status of the nodes.
173 174
    ProcessedMap *_processed;
174 175
    //Indicates if _processed is locally allocated (true) or not.
175 176
    bool local_processed;
176 177

	
177 178
    std::vector<typename Digraph::OutArcIt> _stack;
178 179
    int _stack_head;
179 180

	
180 181
    //Creates the maps if necessary.
181 182
    void create_maps()
182 183
    {
183 184
      if(!_pred) {
184 185
        local_pred = true;
185 186
        _pred = Traits::createPredMap(*G);
186 187
      }
187 188
      if(!_dist) {
188 189
        local_dist = true;
189 190
        _dist = Traits::createDistMap(*G);
190 191
      }
191 192
      if(!_reached) {
192 193
        local_reached = true;
193 194
        _reached = Traits::createReachedMap(*G);
194 195
      }
195 196
      if(!_processed) {
196 197
        local_processed = true;
197 198
        _processed = Traits::createProcessedMap(*G);
198 199
      }
199 200
    }
200 201

	
201 202
  protected:
202 203

	
203 204
    Dfs() {}
204 205

	
205 206
  public:
206 207

	
207 208
    typedef Dfs Create;
208 209

	
209 210
    ///\name Named Template Parameters
210 211

	
211 212
    ///@{
212 213

	
213 214
    template <class T>
214 215
    struct SetPredMapTraits : public Traits {
215 216
      typedef T PredMap;
216 217
      static PredMap *createPredMap(const Digraph &)
217 218
      {
218 219
        LEMON_ASSERT(false, "PredMap is not initialized");
219 220
        return 0; // ignore warnings
220 221
      }
221 222
    };
222 223
    ///\brief \ref named-templ-param "Named parameter" for setting
223 224
    ///\c PredMap type.
224 225
    ///
225 226
    ///\ref named-templ-param "Named parameter" for setting
226 227
    ///\c PredMap type.
227
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
228
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
228 229
    template <class T>
229 230
    struct SetPredMap : public Dfs<Digraph, SetPredMapTraits<T> > {
230 231
      typedef Dfs<Digraph, SetPredMapTraits<T> > Create;
231 232
    };
232 233

	
233 234
    template <class T>
234 235
    struct SetDistMapTraits : public Traits {
235 236
      typedef T DistMap;
236 237
      static DistMap *createDistMap(const Digraph &)
237 238
      {
238 239
        LEMON_ASSERT(false, "DistMap is not initialized");
239 240
        return 0; // ignore warnings
240 241
      }
241 242
    };
242 243
    ///\brief \ref named-templ-param "Named parameter" for setting
243 244
    ///\c DistMap type.
244 245
    ///
245 246
    ///\ref named-templ-param "Named parameter" for setting
246 247
    ///\c DistMap type.
247
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
248
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
248 249
    template <class T>
249 250
    struct SetDistMap : public Dfs< Digraph, SetDistMapTraits<T> > {
250 251
      typedef Dfs<Digraph, SetDistMapTraits<T> > Create;
251 252
    };
252 253

	
253 254
    template <class T>
254 255
    struct SetReachedMapTraits : public Traits {
255 256
      typedef T ReachedMap;
256 257
      static ReachedMap *createReachedMap(const Digraph &)
257 258
      {
258 259
        LEMON_ASSERT(false, "ReachedMap is not initialized");
259 260
        return 0; // ignore warnings
260 261
      }
261 262
    };
262 263
    ///\brief \ref named-templ-param "Named parameter" for setting
263 264
    ///\c ReachedMap type.
264 265
    ///
265 266
    ///\ref named-templ-param "Named parameter" for setting
266 267
    ///\c ReachedMap type.
267
    ///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
268
    ///It must conform to the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
268 269
    template <class T>
269 270
    struct SetReachedMap : public Dfs< Digraph, SetReachedMapTraits<T> > {
270 271
      typedef Dfs< Digraph, SetReachedMapTraits<T> > Create;
271 272
    };
272 273

	
273 274
    template <class T>
274 275
    struct SetProcessedMapTraits : public Traits {
275 276
      typedef T ProcessedMap;
276 277
      static ProcessedMap *createProcessedMap(const Digraph &)
277 278
      {
278 279
        LEMON_ASSERT(false, "ProcessedMap is not initialized");
279 280
        return 0; // ignore warnings
280 281
      }
281 282
    };
282 283
    ///\brief \ref named-templ-param "Named parameter" for setting
283 284
    ///\c ProcessedMap type.
284 285
    ///
285 286
    ///\ref named-templ-param "Named parameter" for setting
286 287
    ///\c ProcessedMap type.
287
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
288
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
288 289
    template <class T>
289 290
    struct SetProcessedMap : public Dfs< Digraph, SetProcessedMapTraits<T> > {
290 291
      typedef Dfs< Digraph, SetProcessedMapTraits<T> > Create;
291 292
    };
292 293

	
293 294
    struct SetStandardProcessedMapTraits : public Traits {
294 295
      typedef typename Digraph::template NodeMap<bool> ProcessedMap;
295 296
      static ProcessedMap *createProcessedMap(const Digraph &g)
296 297
      {
297 298
        return new ProcessedMap(g);
298 299
      }
299 300
    };
300 301
    ///\brief \ref named-templ-param "Named parameter" for setting
301 302
    ///\c ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>.
302 303
    ///
303 304
    ///\ref named-templ-param "Named parameter" for setting
304 305
    ///\c ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>.
305 306
    ///If you don't set it explicitly, it will be automatically allocated.
306 307
    struct SetStandardProcessedMap :
307 308
      public Dfs< Digraph, SetStandardProcessedMapTraits > {
308 309
      typedef Dfs< Digraph, SetStandardProcessedMapTraits > Create;
309 310
    };
310 311

	
311 312
    ///@}
312 313

	
313 314
  public:
314 315

	
315 316
    ///Constructor.
316 317

	
317 318
    ///Constructor.
318 319
    ///\param g The digraph the algorithm runs on.
319 320
    Dfs(const Digraph &g) :
320 321
      G(&g),
321 322
      _pred(NULL), local_pred(false),
322 323
      _dist(NULL), local_dist(false),
323 324
      _reached(NULL), local_reached(false),
324 325
      _processed(NULL), local_processed(false)
325 326
    { }
326 327

	
327 328
    ///Destructor.
328 329
    ~Dfs()
329 330
    {
330 331
      if(local_pred) delete _pred;
331 332
      if(local_dist) delete _dist;
332 333
      if(local_reached) delete _reached;
333 334
      if(local_processed) delete _processed;
334 335
    }
335 336

	
336 337
    ///Sets the map that stores the predecessor arcs.
337 338

	
338 339
    ///Sets the map that stores the predecessor arcs.
339 340
    ///If you don't use this function before calling \ref run(Node) "run()"
340 341
    ///or \ref init(), an instance will be allocated automatically.
341 342
    ///The destructor deallocates this automatically allocated map,
342 343
    ///of course.
343 344
    ///\return <tt> (*this) </tt>
344 345
    Dfs &predMap(PredMap &m)
345 346
    {
346 347
      if(local_pred) {
347 348
        delete _pred;
348 349
        local_pred=false;
349 350
      }
350 351
      _pred = &m;
351 352
      return *this;
352 353
    }
353 354

	
354 355
    ///Sets the map that indicates which nodes are reached.
355 356

	
356 357
    ///Sets the map that indicates which nodes are reached.
357 358
    ///If you don't use this function before calling \ref run(Node) "run()"
358 359
    ///or \ref init(), an instance will be allocated automatically.
359 360
    ///The destructor deallocates this automatically allocated map,
360 361
    ///of course.
361 362
    ///\return <tt> (*this) </tt>
362 363
    Dfs &reachedMap(ReachedMap &m)
363 364
    {
364 365
      if(local_reached) {
365 366
        delete _reached;
366 367
        local_reached=false;
367 368
      }
368 369
      _reached = &m;
369 370
      return *this;
370 371
    }
371 372

	
372 373
    ///Sets the map that indicates which nodes are processed.
373 374

	
374 375
    ///Sets the map that indicates which nodes are processed.
375 376
    ///If you don't use this function before calling \ref run(Node) "run()"
376 377
    ///or \ref init(), an instance will be allocated automatically.
377 378
    ///The destructor deallocates this automatically allocated map,
378 379
    ///of course.
379 380
    ///\return <tt> (*this) </tt>
380 381
    Dfs &processedMap(ProcessedMap &m)
381 382
    {
382 383
      if(local_processed) {
383 384
        delete _processed;
384 385
        local_processed=false;
385 386
      }
386 387
      _processed = &m;
387 388
      return *this;
388 389
    }
389 390

	
390 391
    ///Sets the map that stores the distances of the nodes.
391 392

	
392 393
    ///Sets the map that stores the distances of the nodes calculated by
393 394
    ///the algorithm.
394 395
    ///If you don't use this function before calling \ref run(Node) "run()"
395 396
    ///or \ref init(), an instance will be allocated automatically.
396 397
    ///The destructor deallocates this automatically allocated map,
397 398
    ///of course.
398 399
    ///\return <tt> (*this) </tt>
399 400
    Dfs &distMap(DistMap &m)
400 401
    {
401 402
      if(local_dist) {
402 403
        delete _dist;
403 404
        local_dist=false;
404 405
      }
405 406
      _dist = &m;
406 407
      return *this;
407 408
    }
408 409

	
409 410
  public:
410 411

	
411 412
    ///\name Execution Control
412 413
    ///The simplest way to execute the DFS algorithm is to use one of the
413 414
    ///member functions called \ref run(Node) "run()".\n
414
    ///If you need more control on the execution, first you have to call
415
    ///\ref init(), then you can add a source node with \ref addSource()
415
    ///If you need better control on the execution, you have to call
416
    ///\ref init() first, then you can add a source node with \ref addSource()
416 417
    ///and perform the actual computation with \ref start().
417 418
    ///This procedure can be repeated if there are nodes that have not
418 419
    ///been reached.
419 420

	
420 421
    ///@{
421 422

	
422 423
    ///\brief Initializes the internal data structures.
423 424
    ///
424 425
    ///Initializes the internal data structures.
425 426
    void init()
426 427
    {
427 428
      create_maps();
428 429
      _stack.resize(countNodes(*G));
429 430
      _stack_head=-1;
430 431
      for ( NodeIt u(*G) ; u!=INVALID ; ++u ) {
431 432
        _pred->set(u,INVALID);
432 433
        _reached->set(u,false);
433 434
        _processed->set(u,false);
434 435
      }
435 436
    }
436 437

	
437 438
    ///Adds a new source node.
438 439

	
439 440
    ///Adds a new source node to the set of nodes to be processed.
440 441
    ///
441 442
    ///\pre The stack must be empty. Otherwise the algorithm gives
442 443
    ///wrong results. (One of the outgoing arcs of all the source nodes
443 444
    ///except for the last one will not be visited and distances will
444 445
    ///also be wrong.)
445 446
    void addSource(Node s)
446 447
    {
447 448
      LEMON_DEBUG(emptyQueue(), "The stack is not empty.");
448 449
      if(!(*_reached)[s])
449 450
        {
450 451
          _reached->set(s,true);
451 452
          _pred->set(s,INVALID);
452 453
          OutArcIt e(*G,s);
453 454
          if(e!=INVALID) {
454 455
            _stack[++_stack_head]=e;
455 456
            _dist->set(s,_stack_head);
456 457
          }
457 458
          else {
458 459
            _processed->set(s,true);
459 460
            _dist->set(s,0);
460 461
          }
461 462
        }
462 463
    }
463 464

	
464 465
    ///Processes the next arc.
465 466

	
466 467
    ///Processes the next arc.
467 468
    ///
468 469
    ///\return The processed arc.
469 470
    ///
470 471
    ///\pre The stack must not be empty.
471 472
    Arc processNextArc()
472 473
    {
473 474
      Node m;
474 475
      Arc e=_stack[_stack_head];
475 476
      if(!(*_reached)[m=G->target(e)]) {
476 477
        _pred->set(m,e);
477 478
        _reached->set(m,true);
478 479
        ++_stack_head;
479 480
        _stack[_stack_head] = OutArcIt(*G, m);
480 481
        _dist->set(m,_stack_head);
481 482
      }
482 483
      else {
483 484
        m=G->source(e);
484 485
        ++_stack[_stack_head];
485 486
      }
486 487
      while(_stack_head>=0 && _stack[_stack_head]==INVALID) {
487 488
        _processed->set(m,true);
488 489
        --_stack_head;
489 490
        if(_stack_head>=0) {
490 491
          m=G->source(_stack[_stack_head]);
491 492
          ++_stack[_stack_head];
492 493
        }
493 494
      }
494 495
      return e;
495 496
    }
496 497

	
497 498
    ///Next arc to be processed.
498 499

	
499 500
    ///Next arc to be processed.
500 501
    ///
501 502
    ///\return The next arc to be processed or \c INVALID if the stack
502 503
    ///is empty.
503 504
    OutArcIt nextArc() const
504 505
    {
505 506
      return _stack_head>=0?_stack[_stack_head]:INVALID;
506 507
    }
507 508

	
508 509
    ///Returns \c false if there are nodes to be processed.
509 510

	
510 511
    ///Returns \c false if there are nodes to be processed
511 512
    ///in the queue (stack).
512 513
    bool emptyQueue() const { return _stack_head<0; }
513 514

	
514 515
    ///Returns the number of the nodes to be processed.
515 516

	
516 517
    ///Returns the number of the nodes to be processed
517 518
    ///in the queue (stack).
518 519
    int queueSize() const { return _stack_head+1; }
519 520

	
520 521
    ///Executes the algorithm.
521 522

	
522 523
    ///Executes the algorithm.
523 524
    ///
524 525
    ///This method runs the %DFS algorithm from the root node
525 526
    ///in order to compute the DFS path to each node.
526 527
    ///
527 528
    /// The algorithm computes
528 529
    ///- the %DFS tree,
529 530
    ///- the distance of each node from the root in the %DFS tree.
530 531
    ///
531 532
    ///\pre init() must be called and a root node should be
532 533
    ///added with addSource() before using this function.
533 534
    ///
534 535
    ///\note <tt>d.start()</tt> is just a shortcut of the following code.
535 536
    ///\code
536 537
    ///  while ( !d.emptyQueue() ) {
537 538
    ///    d.processNextArc();
538 539
    ///  }
539 540
    ///\endcode
540 541
    void start()
541 542
    {
542 543
      while ( !emptyQueue() ) processNextArc();
543 544
    }
544 545

	
545 546
    ///Executes the algorithm until the given target node is reached.
546 547

	
547 548
    ///Executes the algorithm until the given target node is reached.
548 549
    ///
549 550
    ///This method runs the %DFS algorithm from the root node
550 551
    ///in order to compute the DFS path to \c t.
551 552
    ///
552 553
    ///The algorithm computes
553 554
    ///- the %DFS path to \c t,
554 555
    ///- the distance of \c t from the root in the %DFS tree.
555 556
    ///
556 557
    ///\pre init() must be called and a root node should be
557 558
    ///added with addSource() before using this function.
558 559
    void start(Node t)
559 560
    {
560 561
      while ( !emptyQueue() && G->target(_stack[_stack_head])!=t )
561 562
        processNextArc();
562 563
    }
563 564

	
564 565
    ///Executes the algorithm until a condition is met.
565 566

	
566 567
    ///Executes the algorithm until a condition is met.
567 568
    ///
568 569
    ///This method runs the %DFS algorithm from the root node
569 570
    ///until an arc \c a with <tt>am[a]</tt> true is found.
570 571
    ///
571 572
    ///\param am A \c bool (or convertible) arc map. The algorithm
572 573
    ///will stop when it reaches an arc \c a with <tt>am[a]</tt> true.
573 574
    ///
574 575
    ///\return The reached arc \c a with <tt>am[a]</tt> true or
575 576
    ///\c INVALID if no such arc was found.
576 577
    ///
577 578
    ///\pre init() must be called and a root node should be
578 579
    ///added with addSource() before using this function.
579 580
    ///
580 581
    ///\warning Contrary to \ref Bfs and \ref Dijkstra, \c am is an arc map,
581 582
    ///not a node map.
582 583
    template<class ArcBoolMap>
583 584
    Arc start(const ArcBoolMap &am)
584 585
    {
585 586
      while ( !emptyQueue() && !am[_stack[_stack_head]] )
586 587
        processNextArc();
587 588
      return emptyQueue() ? INVALID : _stack[_stack_head];
588 589
    }
589 590

	
590 591
    ///Runs the algorithm from the given source node.
591 592

	
592 593
    ///This method runs the %DFS algorithm from node \c s
593 594
    ///in order to compute the DFS path to each node.
594 595
    ///
595 596
    ///The algorithm computes
596 597
    ///- the %DFS tree,
597 598
    ///- the distance of each node from the root in the %DFS tree.
598 599
    ///
599 600
    ///\note <tt>d.run(s)</tt> is just a shortcut of the following code.
600 601
    ///\code
601 602
    ///  d.init();
602 603
    ///  d.addSource(s);
603 604
    ///  d.start();
604 605
    ///\endcode
605 606
    void run(Node s) {
606 607
      init();
607 608
      addSource(s);
608 609
      start();
609 610
    }
610 611

	
611 612
    ///Finds the %DFS path between \c s and \c t.
612 613

	
613 614
    ///This method runs the %DFS algorithm from node \c s
614 615
    ///in order to compute the DFS path to node \c t
615 616
    ///(it stops searching when \c t is processed)
616 617
    ///
617 618
    ///\return \c true if \c t is reachable form \c s.
618 619
    ///
619 620
    ///\note Apart from the return value, <tt>d.run(s,t)</tt> is
620 621
    ///just a shortcut of the following code.
621 622
    ///\code
622 623
    ///  d.init();
623 624
    ///  d.addSource(s);
624 625
    ///  d.start(t);
625 626
    ///\endcode
626 627
    bool run(Node s,Node t) {
627 628
      init();
628 629
      addSource(s);
629 630
      start(t);
630 631
      return reached(t);
631 632
    }
632 633

	
633 634
    ///Runs the algorithm to visit all nodes in the digraph.
634 635

	
635 636
    ///This method runs the %DFS algorithm in order to compute the
636 637
    ///%DFS path to each node.
637 638
    ///
638 639
    ///The algorithm computes
639 640
    ///- the %DFS tree (forest),
640 641
    ///- the distance of each node from the root(s) in the %DFS tree.
641 642
    ///
642 643
    ///\note <tt>d.run()</tt> is just a shortcut of the following code.
643 644
    ///\code
644 645
    ///  d.init();
645 646
    ///  for (NodeIt n(digraph); n != INVALID; ++n) {
646 647
    ///    if (!d.reached(n)) {
647 648
    ///      d.addSource(n);
648 649
    ///      d.start();
649 650
    ///    }
650 651
    ///  }
651 652
    ///\endcode
652 653
    void run() {
653 654
      init();
654 655
      for (NodeIt it(*G); it != INVALID; ++it) {
655 656
        if (!reached(it)) {
656 657
          addSource(it);
657 658
          start();
658 659
        }
659 660
      }
660 661
    }
661 662

	
662 663
    ///@}
663 664

	
664 665
    ///\name Query Functions
665 666
    ///The results of the DFS algorithm can be obtained using these
666 667
    ///functions.\n
667 668
    ///Either \ref run(Node) "run()" or \ref start() should be called
668 669
    ///before using them.
669 670

	
670 671
    ///@{
671 672

	
672
    ///The DFS path to a node.
673
    ///The DFS path to the given node.
673 674

	
674
    ///Returns the DFS path to a node.
675
    ///Returns the DFS path to the given node from the root(s).
675 676
    ///
676 677
    ///\warning \c t should be reached from the root(s).
677 678
    ///
678 679
    ///\pre Either \ref run(Node) "run()" or \ref init()
679 680
    ///must be called before using this function.
680 681
    Path path(Node t) const { return Path(*G, *_pred, t); }
681 682

	
682
    ///The distance of a node from the root(s).
683
    ///The distance of the given node from the root(s).
683 684

	
684
    ///Returns the distance of a node from the root(s).
685
    ///Returns the distance of the given node from the root(s).
685 686
    ///
686 687
    ///\warning If node \c v is not reached from the root(s), then
687 688
    ///the return value of this function is undefined.
688 689
    ///
689 690
    ///\pre Either \ref run(Node) "run()" or \ref init()
690 691
    ///must be called before using this function.
691 692
    int dist(Node v) const { return (*_dist)[v]; }
692 693

	
693
    ///Returns the 'previous arc' of the %DFS tree for a node.
694
    ///Returns the 'previous arc' of the %DFS tree for the given node.
694 695

	
695 696
    ///This function returns the 'previous arc' of the %DFS tree for the
696 697
    ///node \c v, i.e. it returns the last arc of a %DFS path from a
697 698
    ///root to \c v. It is \c INVALID if \c v is not reached from the
698 699
    ///root(s) or if \c v is a root.
699 700
    ///
700 701
    ///The %DFS tree used here is equal to the %DFS tree used in
701
    ///\ref predNode().
702
    ///\ref predNode() and \ref predMap().
702 703
    ///
703 704
    ///\pre Either \ref run(Node) "run()" or \ref init()
704 705
    ///must be called before using this function.
705 706
    Arc predArc(Node v) const { return (*_pred)[v];}
706 707

	
707
    ///Returns the 'previous node' of the %DFS tree.
708
    ///Returns the 'previous node' of the %DFS tree for the given node.
708 709

	
709 710
    ///This function returns the 'previous node' of the %DFS
710 711
    ///tree for the node \c v, i.e. it returns the last but one node
711
    ///from a %DFS path from a root to \c v. It is \c INVALID
712
    ///of a %DFS path from a root to \c v. It is \c INVALID
712 713
    ///if \c v is not reached from the root(s) or if \c v is a root.
713 714
    ///
714 715
    ///The %DFS tree used here is equal to the %DFS tree used in
715
    ///\ref predArc().
716
    ///\ref predArc() and \ref predMap().
716 717
    ///
717 718
    ///\pre Either \ref run(Node) "run()" or \ref init()
718 719
    ///must be called before using this function.
719 720
    Node predNode(Node v) const { return (*_pred)[v]==INVALID ? INVALID:
720 721
                                  G->source((*_pred)[v]); }
721 722

	
722 723
    ///\brief Returns a const reference to the node map that stores the
723 724
    ///distances of the nodes.
724 725
    ///
725 726
    ///Returns a const reference to the node map that stores the
726 727
    ///distances of the nodes calculated by the algorithm.
727 728
    ///
728 729
    ///\pre Either \ref run(Node) "run()" or \ref init()
729 730
    ///must be called before using this function.
730 731
    const DistMap &distMap() const { return *_dist;}
731 732

	
732 733
    ///\brief Returns a const reference to the node map that stores the
733 734
    ///predecessor arcs.
734 735
    ///
735 736
    ///Returns a const reference to the node map that stores the predecessor
736
    ///arcs, which form the DFS tree.
737
    ///arcs, which form the DFS tree (forest).
737 738
    ///
738 739
    ///\pre Either \ref run(Node) "run()" or \ref init()
739 740
    ///must be called before using this function.
740 741
    const PredMap &predMap() const { return *_pred;}
741 742

	
742
    ///Checks if a node is reached from the root(s).
743
    ///Checks if the given node. node is reached from the root(s).
743 744

	
744 745
    ///Returns \c true if \c v is reached from the root(s).
745 746
    ///
746 747
    ///\pre Either \ref run(Node) "run()" or \ref init()
747 748
    ///must be called before using this function.
748 749
    bool reached(Node v) const { return (*_reached)[v]; }
749 750

	
750 751
    ///@}
751 752
  };
752 753

	
753 754
  ///Default traits class of dfs() function.
754 755

	
755 756
  ///Default traits class of dfs() function.
756 757
  ///\tparam GR Digraph type.
757 758
  template<class GR>
758 759
  struct DfsWizardDefaultTraits
759 760
  {
760 761
    ///The type of the digraph the algorithm runs on.
761 762
    typedef GR Digraph;
762 763

	
763 764
    ///\brief The type of the map that stores the predecessor
764 765
    ///arcs of the %DFS paths.
765 766
    ///
766 767
    ///The type of the map that stores the predecessor
767 768
    ///arcs of the %DFS paths.
768
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
769
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
769 770
    typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap;
770 771
    ///Instantiates a PredMap.
771 772

	
772 773
    ///This function instantiates a PredMap.
773 774
    ///\param g is the digraph, to which we would like to define the
774 775
    ///PredMap.
775 776
    static PredMap *createPredMap(const Digraph &g)
776 777
    {
777 778
      return new PredMap(g);
778 779
    }
779 780

	
780 781
    ///The type of the map that indicates which nodes are processed.
781 782

	
782 783
    ///The type of the map that indicates which nodes are processed.
783
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
784
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
784 785
    ///By default it is a NullMap.
785 786
    typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
786 787
    ///Instantiates a ProcessedMap.
787 788

	
788 789
    ///This function instantiates a ProcessedMap.
789 790
    ///\param g is the digraph, to which
790 791
    ///we would like to define the ProcessedMap.
791 792
#ifdef DOXYGEN
792 793
    static ProcessedMap *createProcessedMap(const Digraph &g)
793 794
#else
794 795
    static ProcessedMap *createProcessedMap(const Digraph &)
795 796
#endif
796 797
    {
797 798
      return new ProcessedMap();
798 799
    }
799 800

	
800 801
    ///The type of the map that indicates which nodes are reached.
801 802

	
802 803
    ///The type of the map that indicates which nodes are reached.
803
    ///It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
804
    ///It must conform to the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
804 805
    typedef typename Digraph::template NodeMap<bool> ReachedMap;
805 806
    ///Instantiates a ReachedMap.
806 807

	
807 808
    ///This function instantiates a ReachedMap.
808 809
    ///\param g is the digraph, to which
809 810
    ///we would like to define the ReachedMap.
810 811
    static ReachedMap *createReachedMap(const Digraph &g)
811 812
    {
812 813
      return new ReachedMap(g);
813 814
    }
814 815

	
815 816
    ///The type of the map that stores the distances of the nodes.
816 817

	
817 818
    ///The type of the map that stores the distances of the nodes.
818
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
819
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
819 820
    typedef typename Digraph::template NodeMap<int> DistMap;
820 821
    ///Instantiates a DistMap.
821 822

	
822 823
    ///This function instantiates a DistMap.
823 824
    ///\param g is the digraph, to which we would like to define
824 825
    ///the DistMap
825 826
    static DistMap *createDistMap(const Digraph &g)
826 827
    {
827 828
      return new DistMap(g);
828 829
    }
829 830

	
830 831
    ///The type of the DFS paths.
831 832

	
832 833
    ///The type of the DFS paths.
833
    ///It must meet the \ref concepts::Path "Path" concept.
834
    ///It must conform to the \ref concepts::Path "Path" concept.
834 835
    typedef lemon::Path<Digraph> Path;
835 836
  };
836 837

	
837 838
  /// Default traits class used by DfsWizard
838 839

	
839
  /// To make it easier to use Dfs algorithm
840
  /// we have created a wizard class.
841
  /// This \ref DfsWizard class needs default traits,
842
  /// as well as the \ref Dfs class.
843
  /// The \ref DfsWizardBase is a class to be the default traits of the
844
  /// \ref DfsWizard class.
840
  /// Default traits class used by DfsWizard.
841
  /// \tparam GR The type of the digraph.
845 842
  template<class GR>
846 843
  class DfsWizardBase : public DfsWizardDefaultTraits<GR>
847 844
  {
848 845

	
849 846
    typedef DfsWizardDefaultTraits<GR> Base;
850 847
  protected:
851 848
    //The type of the nodes in the digraph.
852 849
    typedef typename Base::Digraph::Node Node;
853 850

	
854 851
    //Pointer to the digraph the algorithm runs on.
855 852
    void *_g;
856 853
    //Pointer to the map of reached nodes.
857 854
    void *_reached;
858 855
    //Pointer to the map of processed nodes.
859 856
    void *_processed;
860 857
    //Pointer to the map of predecessors arcs.
861 858
    void *_pred;
862 859
    //Pointer to the map of distances.
863 860
    void *_dist;
864 861
    //Pointer to the DFS path to the target node.
865 862
    void *_path;
866 863
    //Pointer to the distance of the target node.
867 864
    int *_di;
868 865

	
869 866
    public:
870 867
    /// Constructor.
871 868

	
872
    /// This constructor does not require parameters, therefore it initiates
869
    /// This constructor does not require parameters, it initiates
873 870
    /// all of the attributes to \c 0.
874 871
    DfsWizardBase() : _g(0), _reached(0), _processed(0), _pred(0),
875 872
                      _dist(0), _path(0), _di(0) {}
876 873

	
877 874
    /// Constructor.
878 875

	
879 876
    /// This constructor requires one parameter,
880 877
    /// others are initiated to \c 0.
881 878
    /// \param g The digraph the algorithm runs on.
882 879
    DfsWizardBase(const GR &g) :
883 880
      _g(reinterpret_cast<void*>(const_cast<GR*>(&g))),
884 881
      _reached(0), _processed(0), _pred(0), _dist(0),  _path(0), _di(0) {}
885 882

	
886 883
  };
887 884

	
888 885
  /// Auxiliary class for the function-type interface of DFS algorithm.
889 886

	
890 887
  /// This auxiliary class is created to implement the
891 888
  /// \ref dfs() "function-type interface" of \ref Dfs algorithm.
892 889
  /// It does not have own \ref run(Node) "run()" method, it uses the
893 890
  /// functions and features of the plain \ref Dfs.
894 891
  ///
895 892
  /// This class should only be used through the \ref dfs() function,
896 893
  /// which makes it easier to use the algorithm.
897 894
  template<class TR>
898 895
  class DfsWizard : public TR
899 896
  {
900 897
    typedef TR Base;
901 898

	
902
    ///The type of the digraph the algorithm runs on.
903 899
    typedef typename TR::Digraph Digraph;
904 900

	
905 901
    typedef typename Digraph::Node Node;
906 902
    typedef typename Digraph::NodeIt NodeIt;
907 903
    typedef typename Digraph::Arc Arc;
908 904
    typedef typename Digraph::OutArcIt OutArcIt;
909 905

	
910
    ///\brief The type of the map that stores the predecessor
911
    ///arcs of the DFS paths.
912 906
    typedef typename TR::PredMap PredMap;
913
    ///\brief The type of the map that stores the distances of the nodes.
914 907
    typedef typename TR::DistMap DistMap;
915
    ///\brief The type of the map that indicates which nodes are reached.
916 908
    typedef typename TR::ReachedMap ReachedMap;
917
    ///\brief The type of the map that indicates which nodes are processed.
918 909
    typedef typename TR::ProcessedMap ProcessedMap;
919
    ///The type of the DFS paths
920 910
    typedef typename TR::Path Path;
921 911

	
922 912
  public:
923 913

	
924 914
    /// Constructor.
925 915
    DfsWizard() : TR() {}
926 916

	
927 917
    /// Constructor that requires parameters.
928 918

	
929 919
    /// Constructor that requires parameters.
930 920
    /// These parameters will be the default values for the traits class.
931 921
    /// \param g The digraph the algorithm runs on.
932 922
    DfsWizard(const Digraph &g) :
933 923
      TR(g) {}
934 924

	
935 925
    ///Copy constructor
936 926
    DfsWizard(const TR &b) : TR(b) {}
937 927

	
938 928
    ~DfsWizard() {}
939 929

	
940 930
    ///Runs DFS algorithm from the given source node.
941 931

	
942 932
    ///This method runs DFS algorithm from node \c s
943 933
    ///in order to compute the DFS path to each node.
944 934
    void run(Node s)
945 935
    {
946 936
      Dfs<Digraph,TR> alg(*reinterpret_cast<const Digraph*>(Base::_g));
947 937
      if (Base::_pred)
948 938
        alg.predMap(*reinterpret_cast<PredMap*>(Base::_pred));
949 939
      if (Base::_dist)
950 940
        alg.distMap(*reinterpret_cast<DistMap*>(Base::_dist));
951 941
      if (Base::_reached)
952 942
        alg.reachedMap(*reinterpret_cast<ReachedMap*>(Base::_reached));
953 943
      if (Base::_processed)
954 944
        alg.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed));
955 945
      if (s!=INVALID)
956 946
        alg.run(s);
957 947
      else
958 948
        alg.run();
959 949
    }
960 950

	
961 951
    ///Finds the DFS path between \c s and \c t.
962 952

	
963 953
    ///This method runs DFS algorithm from node \c s
964 954
    ///in order to compute the DFS path to node \c t
965 955
    ///(it stops searching when \c t is processed).
966 956
    ///
967 957
    ///\return \c true if \c t is reachable form \c s.
968 958
    bool run(Node s, Node t)
969 959
    {
970 960
      Dfs<Digraph,TR> alg(*reinterpret_cast<const Digraph*>(Base::_g));
971 961
      if (Base::_pred)
972 962
        alg.predMap(*reinterpret_cast<PredMap*>(Base::_pred));
973 963
      if (Base::_dist)
974 964
        alg.distMap(*reinterpret_cast<DistMap*>(Base::_dist));
975 965
      if (Base::_reached)
976 966
        alg.reachedMap(*reinterpret_cast<ReachedMap*>(Base::_reached));
977 967
      if (Base::_processed)
978 968
        alg.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed));
979 969
      alg.run(s,t);
980 970
      if (Base::_path)
981 971
        *reinterpret_cast<Path*>(Base::_path) = alg.path(t);
982 972
      if (Base::_di)
983 973
        *Base::_di = alg.dist(t);
984 974
      return alg.reached(t);
985 975
      }
986 976

	
987 977
    ///Runs DFS algorithm to visit all nodes in the digraph.
988 978

	
989 979
    ///This method runs DFS algorithm in order to compute
990 980
    ///the DFS path to each node.
991 981
    void run()
992 982
    {
993 983
      run(INVALID);
994 984
    }
995 985

	
996 986
    template<class T>
997 987
    struct SetPredMapBase : public Base {
998 988
      typedef T PredMap;
999 989
      static PredMap *createPredMap(const Digraph &) { return 0; };
1000 990
      SetPredMapBase(const TR &b) : TR(b) {}
1001 991
    };
1002
    ///\brief \ref named-func-param "Named parameter"
1003
    ///for setting PredMap object.
992

	
993
    ///\brief \ref named-templ-param "Named parameter" for setting
994
    ///the predecessor map.
1004 995
    ///
1005
    ///\ref named-func-param "Named parameter"
1006
    ///for setting PredMap object.
996
    ///\ref named-templ-param "Named parameter" function for setting
997
    ///the map that stores the predecessor arcs of the nodes.
1007 998
    template<class T>
1008 999
    DfsWizard<SetPredMapBase<T> > predMap(const T &t)
1009 1000
    {
1010 1001
      Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t));
1011 1002
      return DfsWizard<SetPredMapBase<T> >(*this);
1012 1003
    }
1013 1004

	
1014 1005
    template<class T>
1015 1006
    struct SetReachedMapBase : public Base {
1016 1007
      typedef T ReachedMap;
1017 1008
      static ReachedMap *createReachedMap(const Digraph &) { return 0; };
1018 1009
      SetReachedMapBase(const TR &b) : TR(b) {}
1019 1010
    };
1020
    ///\brief \ref named-func-param "Named parameter"
1021
    ///for setting ReachedMap object.
1011

	
1012
    ///\brief \ref named-templ-param "Named parameter" for setting
1013
    ///the reached map.
1022 1014
    ///
1023
    /// \ref named-func-param "Named parameter"
1024
    ///for setting ReachedMap object.
1015
    ///\ref named-templ-param "Named parameter" function for setting
1016
    ///the map that indicates which nodes are reached.
1025 1017
    template<class T>
1026 1018
    DfsWizard<SetReachedMapBase<T> > reachedMap(const T &t)
1027 1019
    {
1028 1020
      Base::_reached=reinterpret_cast<void*>(const_cast<T*>(&t));
1029 1021
      return DfsWizard<SetReachedMapBase<T> >(*this);
1030 1022
    }
1031 1023

	
1032 1024
    template<class T>
1033 1025
    struct SetDistMapBase : public Base {
1034 1026
      typedef T DistMap;
1035 1027
      static DistMap *createDistMap(const Digraph &) { return 0; };
1036 1028
      SetDistMapBase(const TR &b) : TR(b) {}
1037 1029
    };
1038
    ///\brief \ref named-func-param "Named parameter"
1039
    ///for setting DistMap object.
1030

	
1031
    ///\brief \ref named-templ-param "Named parameter" for setting
1032
    ///the distance map.
1040 1033
    ///
1041
    /// \ref named-func-param "Named parameter"
1042
    ///for setting DistMap object.
1034
    ///\ref named-templ-param "Named parameter" function for setting
1035
    ///the map that stores the distances of the nodes calculated
1036
    ///by the algorithm.
1043 1037
    template<class T>
1044 1038
    DfsWizard<SetDistMapBase<T> > distMap(const T &t)
1045 1039
    {
1046 1040
      Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t));
1047 1041
      return DfsWizard<SetDistMapBase<T> >(*this);
1048 1042
    }
1049 1043

	
1050 1044
    template<class T>
1051 1045
    struct SetProcessedMapBase : public Base {
1052 1046
      typedef T ProcessedMap;
1053 1047
      static ProcessedMap *createProcessedMap(const Digraph &) { return 0; };
1054 1048
      SetProcessedMapBase(const TR &b) : TR(b) {}
1055 1049
    };
1056
    ///\brief \ref named-func-param "Named parameter"
1057
    ///for setting ProcessedMap object.
1050

	
1051
    ///\brief \ref named-func-param "Named parameter" for setting
1052
    ///the processed map.
1058 1053
    ///
1059
    /// \ref named-func-param "Named parameter"
1060
    ///for setting ProcessedMap object.
1054
    ///\ref named-templ-param "Named parameter" function for setting
1055
    ///the map that indicates which nodes are processed.
1061 1056
    template<class T>
1062 1057
    DfsWizard<SetProcessedMapBase<T> > processedMap(const T &t)
1063 1058
    {
1064 1059
      Base::_processed=reinterpret_cast<void*>(const_cast<T*>(&t));
1065 1060
      return DfsWizard<SetProcessedMapBase<T> >(*this);
1066 1061
    }
1067 1062

	
1068 1063
    template<class T>
1069 1064
    struct SetPathBase : public Base {
1070 1065
      typedef T Path;
1071 1066
      SetPathBase(const TR &b) : TR(b) {}
1072 1067
    };
1073 1068
    ///\brief \ref named-func-param "Named parameter"
1074 1069
    ///for getting the DFS path to the target node.
1075 1070
    ///
1076 1071
    ///\ref named-func-param "Named parameter"
1077 1072
    ///for getting the DFS path to the target node.
1078 1073
    template<class T>
1079 1074
    DfsWizard<SetPathBase<T> > path(const T &t)
1080 1075
    {
1081 1076
      Base::_path=reinterpret_cast<void*>(const_cast<T*>(&t));
1082 1077
      return DfsWizard<SetPathBase<T> >(*this);
1083 1078
    }
1084 1079

	
1085 1080
    ///\brief \ref named-func-param "Named parameter"
1086 1081
    ///for getting the distance of the target node.
1087 1082
    ///
1088 1083
    ///\ref named-func-param "Named parameter"
1089 1084
    ///for getting the distance of the target node.
1090 1085
    DfsWizard dist(const int &d)
1091 1086
    {
1092 1087
      Base::_di=const_cast<int*>(&d);
1093 1088
      return *this;
1094 1089
    }
1095 1090

	
1096 1091
  };
1097 1092

	
1098 1093
  ///Function-type interface for DFS algorithm.
1099 1094

	
1100 1095
  ///\ingroup search
1101 1096
  ///Function-type interface for DFS algorithm.
1102 1097
  ///
1103 1098
  ///This function also has several \ref named-func-param "named parameters",
1104 1099
  ///they are declared as the members of class \ref DfsWizard.
1105 1100
  ///The following examples show how to use these parameters.
1106 1101
  ///\code
1107 1102
  ///  // Compute the DFS tree
1108 1103
  ///  dfs(g).predMap(preds).distMap(dists).run(s);
1109 1104
  ///
1110 1105
  ///  // Compute the DFS path from s to t
1111 1106
  ///  bool reached = dfs(g).path(p).dist(d).run(s,t);
1112 1107
  ///\endcode
1113 1108
  ///\warning Don't forget to put the \ref DfsWizard::run(Node) "run()"
1114 1109
  ///to the end of the parameter list.
1115 1110
  ///\sa DfsWizard
1116 1111
  ///\sa Dfs
1117 1112
  template<class GR>
1118 1113
  DfsWizard<DfsWizardBase<GR> >
1119 1114
  dfs(const GR &digraph)
1120 1115
  {
1121 1116
    return DfsWizard<DfsWizardBase<GR> >(digraph);
1122 1117
  }
1123 1118

	
1124 1119
#ifdef DOXYGEN
1125 1120
  /// \brief Visitor class for DFS.
1126 1121
  ///
1127 1122
  /// This class defines the interface of the DfsVisit events, and
1128 1123
  /// it could be the base of a real visitor class.
1129 1124
  template <typename GR>
1130 1125
  struct DfsVisitor {
1131 1126
    typedef GR Digraph;
1132 1127
    typedef typename Digraph::Arc Arc;
1133 1128
    typedef typename Digraph::Node Node;
1134 1129
    /// \brief Called for the source node of the DFS.
1135 1130
    ///
1136 1131
    /// This function is called for the source node of the DFS.
1137 1132
    void start(const Node& node) {}
1138 1133
    /// \brief Called when the source node is leaved.
1139 1134
    ///
1140 1135
    /// This function is called when the source node is leaved.
1141 1136
    void stop(const Node& node) {}
1142 1137
    /// \brief Called when a node is reached first time.
1143 1138
    ///
1144 1139
    /// This function is called when a node is reached first time.
1145 1140
    void reach(const Node& node) {}
1146 1141
    /// \brief Called when an arc reaches a new node.
1147 1142
    ///
1148 1143
    /// This function is called when the DFS finds an arc whose target node
1149 1144
    /// is not reached yet.
1150 1145
    void discover(const Arc& arc) {}
1151 1146
    /// \brief Called when an arc is examined but its target node is
1152 1147
    /// already discovered.
1153 1148
    ///
1154 1149
    /// This function is called when an arc is examined but its target node is
1155 1150
    /// already discovered.
1156 1151
    void examine(const Arc& arc) {}
1157 1152
    /// \brief Called when the DFS steps back from a node.
1158 1153
    ///
1159 1154
    /// This function is called when the DFS steps back from a node.
1160 1155
    void leave(const Node& node) {}
1161 1156
    /// \brief Called when the DFS steps back on an arc.
1162 1157
    ///
1163 1158
    /// This function is called when the DFS steps back on an arc.
1164 1159
    void backtrack(const Arc& arc) {}
1165 1160
  };
1166 1161
#else
1167 1162
  template <typename GR>
1168 1163
  struct DfsVisitor {
1169 1164
    typedef GR Digraph;
1170 1165
    typedef typename Digraph::Arc Arc;
1171 1166
    typedef typename Digraph::Node Node;
1172 1167
    void start(const Node&) {}
1173 1168
    void stop(const Node&) {}
1174 1169
    void reach(const Node&) {}
1175 1170
    void discover(const Arc&) {}
1176 1171
    void examine(const Arc&) {}
1177 1172
    void leave(const Node&) {}
1178 1173
    void backtrack(const Arc&) {}
1179 1174

	
1180 1175
    template <typename _Visitor>
1181 1176
    struct Constraints {
1182 1177
      void constraints() {
1183 1178
        Arc arc;
1184 1179
        Node node;
1185 1180
        visitor.start(node);
1186 1181
        visitor.stop(arc);
1187 1182
        visitor.reach(node);
1188 1183
        visitor.discover(arc);
1189 1184
        visitor.examine(arc);
1190 1185
        visitor.leave(node);
1191 1186
        visitor.backtrack(arc);
1192 1187
      }
1193 1188
      _Visitor& visitor;
1194 1189
    };
1195 1190
  };
1196 1191
#endif
1197 1192

	
1198 1193
  /// \brief Default traits class of DfsVisit class.
1199 1194
  ///
1200 1195
  /// Default traits class of DfsVisit class.
1201 1196
  /// \tparam _Digraph The type of the digraph the algorithm runs on.
1202 1197
  template<class GR>
1203 1198
  struct DfsVisitDefaultTraits {
1204 1199

	
1205 1200
    /// \brief The type of the digraph the algorithm runs on.
1206 1201
    typedef GR Digraph;
1207 1202

	
1208 1203
    /// \brief The type of the map that indicates which nodes are reached.
1209 1204
    ///
1210 1205
    /// The type of the map that indicates which nodes are reached.
1211
    /// It must meet the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
1206
    /// It must conform to the \ref concepts::ReadWriteMap "ReadWriteMap" concept.
1212 1207
    typedef typename Digraph::template NodeMap<bool> ReachedMap;
1213 1208

	
1214 1209
    /// \brief Instantiates a ReachedMap.
1215 1210
    ///
1216 1211
    /// This function instantiates a ReachedMap.
1217 1212
    /// \param digraph is the digraph, to which
1218 1213
    /// we would like to define the ReachedMap.
1219 1214
    static ReachedMap *createReachedMap(const Digraph &digraph) {
1220 1215
      return new ReachedMap(digraph);
1221 1216
    }
1222 1217

	
1223 1218
  };
1224 1219

	
1225 1220
  /// \ingroup search
1226 1221
  ///
1227 1222
  /// \brief DFS algorithm class with visitor interface.
1228 1223
  ///
1229 1224
  /// This class provides an efficient implementation of the DFS algorithm
1230 1225
  /// with visitor interface.
1231 1226
  ///
1232 1227
  /// The DfsVisit class provides an alternative interface to the Dfs
1233 1228
  /// class. It works with callback mechanism, the DfsVisit object calls
1234 1229
  /// the member functions of the \c Visitor class on every DFS event.
1235 1230
  ///
1236 1231
  /// This interface of the DFS algorithm should be used in special cases
1237 1232
  /// when extra actions have to be performed in connection with certain
1238 1233
  /// events of the DFS algorithm. Otherwise consider to use Dfs or dfs()
1239 1234
  /// instead.
1240 1235
  ///
1241 1236
  /// \tparam GR The type of the digraph the algorithm runs on.
1242 1237
  /// The default type is \ref ListDigraph.
1243 1238
  /// The value of GR is not used directly by \ref DfsVisit,
1244 1239
  /// it is only passed to \ref DfsVisitDefaultTraits.
1245 1240
  /// \tparam VS The Visitor type that is used by the algorithm.
1246 1241
  /// \ref DfsVisitor "DfsVisitor<GR>" is an empty visitor, which
1247 1242
  /// does not observe the DFS events. If you want to observe the DFS
1248 1243
  /// events, you should implement your own visitor class.
1249 1244
  /// \tparam TR Traits class to set various data types used by the
1250 1245
  /// algorithm. The default traits class is
1251 1246
  /// \ref DfsVisitDefaultTraits "DfsVisitDefaultTraits<GR>".
1252 1247
  /// See \ref DfsVisitDefaultTraits for the documentation of
1253 1248
  /// a DFS visit traits class.
1254 1249
#ifdef DOXYGEN
1255 1250
  template <typename GR, typename VS, typename TR>
1256 1251
#else
1257 1252
  template <typename GR = ListDigraph,
1258 1253
            typename VS = DfsVisitor<GR>,
1259 1254
            typename TR = DfsVisitDefaultTraits<GR> >
1260 1255
#endif
1261 1256
  class DfsVisit {
1262 1257
  public:
1263 1258

	
1264 1259
    ///The traits class.
1265 1260
    typedef TR Traits;
1266 1261

	
1267 1262
    ///The type of the digraph the algorithm runs on.
1268 1263
    typedef typename Traits::Digraph Digraph;
1269 1264

	
1270 1265
    ///The visitor type used by the algorithm.
1271 1266
    typedef VS Visitor;
1272 1267

	
1273 1268
    ///The type of the map that indicates which nodes are reached.
1274 1269
    typedef typename Traits::ReachedMap ReachedMap;
1275 1270

	
1276 1271
  private:
1277 1272

	
1278 1273
    typedef typename Digraph::Node Node;
1279 1274
    typedef typename Digraph::NodeIt NodeIt;
1280 1275
    typedef typename Digraph::Arc Arc;
1281 1276
    typedef typename Digraph::OutArcIt OutArcIt;
1282 1277

	
1283 1278
    //Pointer to the underlying digraph.
1284 1279
    const Digraph *_digraph;
1285 1280
    //Pointer to the visitor object.
1286 1281
    Visitor *_visitor;
1287 1282
    //Pointer to the map of reached status of the nodes.
1288 1283
    ReachedMap *_reached;
1289 1284
    //Indicates if _reached is locally allocated (true) or not.
1290 1285
    bool local_reached;
1291 1286

	
1292 1287
    std::vector<typename Digraph::Arc> _stack;
1293 1288
    int _stack_head;
1294 1289

	
1295 1290
    //Creates the maps if necessary.
1296 1291
    void create_maps() {
1297 1292
      if(!_reached) {
1298 1293
        local_reached = true;
1299 1294
        _reached = Traits::createReachedMap(*_digraph);
1300 1295
      }
1301 1296
    }
1302 1297

	
1303 1298
  protected:
1304 1299

	
1305 1300
    DfsVisit() {}
1306 1301

	
1307 1302
  public:
1308 1303

	
1309 1304
    typedef DfsVisit Create;
1310 1305

	
1311 1306
    /// \name Named Template Parameters
1312 1307

	
1313 1308
    ///@{
1314 1309
    template <class T>
1315 1310
    struct SetReachedMapTraits : public Traits {
1316 1311
      typedef T ReachedMap;
1317 1312
      static ReachedMap *createReachedMap(const Digraph &digraph) {
1318 1313
        LEMON_ASSERT(false, "ReachedMap is not initialized");
1319 1314
        return 0; // ignore warnings
1320 1315
      }
1321 1316
    };
1322 1317
    /// \brief \ref named-templ-param "Named parameter" for setting
1323 1318
    /// ReachedMap type.
1324 1319
    ///
1325 1320
    /// \ref named-templ-param "Named parameter" for setting ReachedMap type.
1326 1321
    template <class T>
1327 1322
    struct SetReachedMap : public DfsVisit< Digraph, Visitor,
1328 1323
                                            SetReachedMapTraits<T> > {
1329 1324
      typedef DfsVisit< Digraph, Visitor, SetReachedMapTraits<T> > Create;
1330 1325
    };
1331 1326
    ///@}
1332 1327

	
1333 1328
  public:
1334 1329

	
1335 1330
    /// \brief Constructor.
1336 1331
    ///
1337 1332
    /// Constructor.
1338 1333
    ///
1339 1334
    /// \param digraph The digraph the algorithm runs on.
1340 1335
    /// \param visitor The visitor object of the algorithm.
1341 1336
    DfsVisit(const Digraph& digraph, Visitor& visitor)
1342 1337
      : _digraph(&digraph), _visitor(&visitor),
1343 1338
        _reached(0), local_reached(false) {}
1344 1339

	
1345 1340
    /// \brief Destructor.
1346 1341
    ~DfsVisit() {
1347 1342
      if(local_reached) delete _reached;
1348 1343
    }
1349 1344

	
1350 1345
    /// \brief Sets the map that indicates which nodes are reached.
1351 1346
    ///
1352 1347
    /// Sets the map that indicates which nodes are reached.
1353 1348
    /// If you don't use this function before calling \ref run(Node) "run()"
1354 1349
    /// or \ref init(), an instance will be allocated automatically.
1355 1350
    /// The destructor deallocates this automatically allocated map,
1356 1351
    /// of course.
1357 1352
    /// \return <tt> (*this) </tt>
1358 1353
    DfsVisit &reachedMap(ReachedMap &m) {
1359 1354
      if(local_reached) {
1360 1355
        delete _reached;
1361 1356
        local_reached=false;
1362 1357
      }
1363 1358
      _reached = &m;
1364 1359
      return *this;
1365 1360
    }
1366 1361

	
1367 1362
  public:
1368 1363

	
1369 1364
    /// \name Execution Control
1370 1365
    /// The simplest way to execute the DFS algorithm is to use one of the
1371 1366
    /// member functions called \ref run(Node) "run()".\n
1372
    /// If you need more control on the execution, first you have to call
1373
    /// \ref init(), then you can add a source node with \ref addSource()
1367
    /// If you need better control on the execution, you have to call
1368
    /// \ref init() first, then you can add a source node with \ref addSource()
1374 1369
    /// and perform the actual computation with \ref start().
1375 1370
    /// This procedure can be repeated if there are nodes that have not
1376 1371
    /// been reached.
1377 1372

	
1378 1373
    /// @{
1379 1374

	
1380 1375
    /// \brief Initializes the internal data structures.
1381 1376
    ///
1382 1377
    /// Initializes the internal data structures.
1383 1378
    void init() {
1384 1379
      create_maps();
1385 1380
      _stack.resize(countNodes(*_digraph));
1386 1381
      _stack_head = -1;
1387 1382
      for (NodeIt u(*_digraph) ; u != INVALID ; ++u) {
1388 1383
        _reached->set(u, false);
1389 1384
      }
1390 1385
    }
1391 1386

	
1392 1387
    /// \brief Adds a new source node.
1393 1388
    ///
1394 1389
    /// Adds a new source node to the set of nodes to be processed.
1395 1390
    ///
1396 1391
    /// \pre The stack must be empty. Otherwise the algorithm gives
1397 1392
    /// wrong results. (One of the outgoing arcs of all the source nodes
1398 1393
    /// except for the last one will not be visited and distances will
1399 1394
    /// also be wrong.)
1400 1395
    void addSource(Node s)
1401 1396
    {
1402 1397
      LEMON_DEBUG(emptyQueue(), "The stack is not empty.");
1403 1398
      if(!(*_reached)[s]) {
1404 1399
          _reached->set(s,true);
1405 1400
          _visitor->start(s);
1406 1401
          _visitor->reach(s);
1407 1402
          Arc e;
1408 1403
          _digraph->firstOut(e, s);
1409 1404
          if (e != INVALID) {
1410 1405
            _stack[++_stack_head] = e;
1411 1406
          } else {
1412 1407
            _visitor->leave(s);
1413 1408
            _visitor->stop(s);
1414 1409
          }
1415 1410
        }
1416 1411
    }
1417 1412

	
1418 1413
    /// \brief Processes the next arc.
1419 1414
    ///
1420 1415
    /// Processes the next arc.
1421 1416
    ///
1422 1417
    /// \return The processed arc.
1423 1418
    ///
1424 1419
    /// \pre The stack must not be empty.
1425 1420
    Arc processNextArc() {
1426 1421
      Arc e = _stack[_stack_head];
1427 1422
      Node m = _digraph->target(e);
1428 1423
      if(!(*_reached)[m]) {
1429 1424
        _visitor->discover(e);
1430 1425
        _visitor->reach(m);
1431 1426
        _reached->set(m, true);
1432 1427
        _digraph->firstOut(_stack[++_stack_head], m);
1433 1428
      } else {
1434 1429
        _visitor->examine(e);
1435 1430
        m = _digraph->source(e);
1436 1431
        _digraph->nextOut(_stack[_stack_head]);
1437 1432
      }
1438 1433
      while (_stack_head>=0 && _stack[_stack_head] == INVALID) {
1439 1434
        _visitor->leave(m);
1440 1435
        --_stack_head;
1441 1436
        if (_stack_head >= 0) {
1442 1437
          _visitor->backtrack(_stack[_stack_head]);
1443 1438
          m = _digraph->source(_stack[_stack_head]);
1444 1439
          _digraph->nextOut(_stack[_stack_head]);
1445 1440
        } else {
1446 1441
          _visitor->stop(m);
1447 1442
        }
1448 1443
      }
1449 1444
      return e;
1450 1445
    }
1451 1446

	
1452 1447
    /// \brief Next arc to be processed.
1453 1448
    ///
1454 1449
    /// Next arc to be processed.
1455 1450
    ///
1456 1451
    /// \return The next arc to be processed or INVALID if the stack is
1457 1452
    /// empty.
1458 1453
    Arc nextArc() const {
1459 1454
      return _stack_head >= 0 ? _stack[_stack_head] : INVALID;
1460 1455
    }
1461 1456

	
1462 1457
    /// \brief Returns \c false if there are nodes
1463 1458
    /// to be processed.
1464 1459
    ///
1465 1460
    /// Returns \c false if there are nodes
1466 1461
    /// to be processed in the queue (stack).
1467 1462
    bool emptyQueue() const { return _stack_head < 0; }
1468 1463

	
1469 1464
    /// \brief Returns the number of the nodes to be processed.
1470 1465
    ///
1471 1466
    /// Returns the number of the nodes to be processed in the queue (stack).
1472 1467
    int queueSize() const { return _stack_head + 1; }
1473 1468

	
1474 1469
    /// \brief Executes the algorithm.
1475 1470
    ///
1476 1471
    /// Executes the algorithm.
1477 1472
    ///
1478 1473
    /// This method runs the %DFS algorithm from the root node
1479 1474
    /// in order to compute the %DFS path to each node.
1480 1475
    ///
1481 1476
    /// The algorithm computes
1482 1477
    /// - the %DFS tree,
1483 1478
    /// - the distance of each node from the root in the %DFS tree.
1484 1479
    ///
1485 1480
    /// \pre init() must be called and a root node should be
1486 1481
    /// added with addSource() before using this function.
1487 1482
    ///
1488 1483
    /// \note <tt>d.start()</tt> is just a shortcut of the following code.
1489 1484
    /// \code
1490 1485
    ///   while ( !d.emptyQueue() ) {
1491 1486
    ///     d.processNextArc();
1492 1487
    ///   }
1493 1488
    /// \endcode
1494 1489
    void start() {
1495 1490
      while ( !emptyQueue() ) processNextArc();
1496 1491
    }
1497 1492

	
1498 1493
    /// \brief Executes the algorithm until the given target node is reached.
1499 1494
    ///
1500 1495
    /// Executes the algorithm until the given target node is reached.
1501 1496
    ///
1502 1497
    /// This method runs the %DFS algorithm from the root node
1503 1498
    /// in order to compute the DFS path to \c t.
1504 1499
    ///
1505 1500
    /// The algorithm computes
1506 1501
    /// - the %DFS path to \c t,
1507 1502
    /// - the distance of \c t from the root in the %DFS tree.
1508 1503
    ///
1509 1504
    /// \pre init() must be called and a root node should be added
1510 1505
    /// with addSource() before using this function.
1511 1506
    void start(Node t) {
1512 1507
      while ( !emptyQueue() && _digraph->target(_stack[_stack_head]) != t )
1513 1508
        processNextArc();
1514 1509
    }
1515 1510

	
1516 1511
    /// \brief Executes the algorithm until a condition is met.
1517 1512
    ///
1518 1513
    /// Executes the algorithm until a condition is met.
1519 1514
    ///
1520 1515
    /// This method runs the %DFS algorithm from the root node
1521 1516
    /// until an arc \c a with <tt>am[a]</tt> true is found.
1522 1517
    ///
1523 1518
    /// \param am A \c bool (or convertible) arc map. The algorithm
1524 1519
    /// will stop when it reaches an arc \c a with <tt>am[a]</tt> true.
1525 1520
    ///
1526 1521
    /// \return The reached arc \c a with <tt>am[a]</tt> true or
1527 1522
    /// \c INVALID if no such arc was found.
1528 1523
    ///
1529 1524
    /// \pre init() must be called and a root node should be added
1530 1525
    /// with addSource() before using this function.
1531 1526
    ///
1532 1527
    /// \warning Contrary to \ref Bfs and \ref Dijkstra, \c am is an arc map,
1533 1528
    /// not a node map.
1534 1529
    template <typename AM>
1535 1530
    Arc start(const AM &am) {
1536 1531
      while ( !emptyQueue() && !am[_stack[_stack_head]] )
1537 1532
        processNextArc();
1538 1533
      return emptyQueue() ? INVALID : _stack[_stack_head];
1539 1534
    }
1540 1535

	
1541 1536
    /// \brief Runs the algorithm from the given source node.
1542 1537
    ///
1543 1538
    /// This method runs the %DFS algorithm from node \c s.
1544 1539
    /// in order to compute the DFS path to each node.
1545 1540
    ///
1546 1541
    /// The algorithm computes
1547 1542
    /// - the %DFS tree,
1548 1543
    /// - the distance of each node from the root in the %DFS tree.
1549 1544
    ///
1550 1545
    /// \note <tt>d.run(s)</tt> is just a shortcut of the following code.
1551 1546
    ///\code
1552 1547
    ///   d.init();
1553 1548
    ///   d.addSource(s);
1554 1549
    ///   d.start();
1555 1550
    ///\endcode
1556 1551
    void run(Node s) {
1557 1552
      init();
1558 1553
      addSource(s);
1559 1554
      start();
1560 1555
    }
1561 1556

	
1562 1557
    /// \brief Finds the %DFS path between \c s and \c t.
1563 1558

	
1564 1559
    /// This method runs the %DFS algorithm from node \c s
1565 1560
    /// in order to compute the DFS path to node \c t
1566 1561
    /// (it stops searching when \c t is processed).
1567 1562
    ///
1568 1563
    /// \return \c true if \c t is reachable form \c s.
1569 1564
    ///
1570 1565
    /// \note Apart from the return value, <tt>d.run(s,t)</tt> is
1571 1566
    /// just a shortcut of the following code.
1572 1567
    ///\code
1573 1568
    ///   d.init();
1574 1569
    ///   d.addSource(s);
1575 1570
    ///   d.start(t);
1576 1571
    ///\endcode
1577 1572
    bool run(Node s,Node t) {
1578 1573
      init();
1579 1574
      addSource(s);
1580 1575
      start(t);
1581 1576
      return reached(t);
1582 1577
    }
1583 1578

	
1584 1579
    /// \brief Runs the algorithm to visit all nodes in the digraph.
1585 1580

	
1586 1581
    /// This method runs the %DFS algorithm in order to
1587 1582
    /// compute the %DFS path to each node.
1588 1583
    ///
1589 1584
    /// The algorithm computes
1590 1585
    /// - the %DFS tree (forest),
1591 1586
    /// - the distance of each node from the root(s) in the %DFS tree.
1592 1587
    ///
1593 1588
    /// \note <tt>d.run()</tt> is just a shortcut of the following code.
1594 1589
    ///\code
1595 1590
    ///   d.init();
1596 1591
    ///   for (NodeIt n(digraph); n != INVALID; ++n) {
1597 1592
    ///     if (!d.reached(n)) {
1598 1593
    ///       d.addSource(n);
1599 1594
    ///       d.start();
1600 1595
    ///     }
1601 1596
    ///   }
1602 1597
    ///\endcode
1603 1598
    void run() {
1604 1599
      init();
1605 1600
      for (NodeIt it(*_digraph); it != INVALID; ++it) {
1606 1601
        if (!reached(it)) {
1607 1602
          addSource(it);
1608 1603
          start();
1609 1604
        }
1610 1605
      }
1611 1606
    }
1612 1607

	
1613 1608
    ///@}
1614 1609

	
1615 1610
    /// \name Query Functions
1616 1611
    /// The results of the DFS algorithm can be obtained using these
1617 1612
    /// functions.\n
1618 1613
    /// Either \ref run(Node) "run()" or \ref start() should be called
1619 1614
    /// before using them.
1620 1615

	
1621 1616
    ///@{
1622 1617

	
1623
    /// \brief Checks if a node is reached from the root(s).
1618
    /// \brief Checks if the given node is reached from the root(s).
1624 1619
    ///
1625 1620
    /// Returns \c true if \c v is reached from the root(s).
1626 1621
    ///
1627 1622
    /// \pre Either \ref run(Node) "run()" or \ref init()
1628 1623
    /// must be called before using this function.
1629 1624
    bool reached(Node v) const { return (*_reached)[v]; }
1630 1625

	
1631 1626
    ///@}
1632 1627

	
1633 1628
  };
1634 1629

	
1635 1630
} //END OF NAMESPACE LEMON
1636 1631

	
1637 1632
#endif
Ignore white space 6 line context
1 1
/* -*- mode: C++; indent-tabs-mode: nil; -*-
2 2
 *
3 3
 * This file is a part of LEMON, a generic C++ optimization library.
4 4
 *
5 5
 * Copyright (C) 2003-2009
6 6
 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 7
 * (Egervary Research Group on Combinatorial Optimization, EGRES).
8 8
 *
9 9
 * Permission to use, modify and distribute this software is granted
10 10
 * provided that this copyright notice appears in all copies. For
11 11
 * precise terms see the accompanying LICENSE file.
12 12
 *
13 13
 * This software is provided "AS IS" with no warranty of any kind,
14 14
 * express or implied, and with no claim as to its suitability for any
15 15
 * purpose.
16 16
 *
17 17
 */
18 18

	
19 19
#ifndef LEMON_DIJKSTRA_H
20 20
#define LEMON_DIJKSTRA_H
21 21

	
22 22
///\ingroup shortest_path
23 23
///\file
24 24
///\brief Dijkstra algorithm.
25 25

	
26 26
#include <limits>
27 27
#include <lemon/list_graph.h>
28 28
#include <lemon/bin_heap.h>
29 29
#include <lemon/bits/path_dump.h>
30 30
#include <lemon/core.h>
31 31
#include <lemon/error.h>
32 32
#include <lemon/maps.h>
33 33
#include <lemon/path.h>
34 34

	
35 35
namespace lemon {
36 36

	
37 37
  /// \brief Default operation traits for the Dijkstra algorithm class.
38 38
  ///
39 39
  /// This operation traits class defines all computational operations and
40 40
  /// constants which are used in the Dijkstra algorithm.
41 41
  template <typename V>
42 42
  struct DijkstraDefaultOperationTraits {
43 43
    /// \e
44 44
    typedef V Value;
45 45
    /// \brief Gives back the zero value of the type.
46 46
    static Value zero() {
47 47
      return static_cast<Value>(0);
48 48
    }
49 49
    /// \brief Gives back the sum of the given two elements.
50 50
    static Value plus(const Value& left, const Value& right) {
51 51
      return left + right;
52 52
    }
53 53
    /// \brief Gives back true only if the first value is less than the second.
54 54
    static bool less(const Value& left, const Value& right) {
55 55
      return left < right;
56 56
    }
57 57
  };
58 58

	
59 59
  ///Default traits class of Dijkstra class.
60 60

	
61 61
  ///Default traits class of Dijkstra class.
62 62
  ///\tparam GR The type of the digraph.
63 63
  ///\tparam LEN The type of the length map.
64 64
  template<typename GR, typename LEN>
65 65
  struct DijkstraDefaultTraits
66 66
  {
67 67
    ///The type of the digraph the algorithm runs on.
68 68
    typedef GR Digraph;
69 69

	
70 70
    ///The type of the map that stores the arc lengths.
71 71

	
72 72
    ///The type of the map that stores the arc lengths.
73
    ///It must meet the \ref concepts::ReadMap "ReadMap" concept.
73
    ///It must conform to the \ref concepts::ReadMap "ReadMap" concept.
74 74
    typedef LEN LengthMap;
75
    ///The type of the length of the arcs.
75
    ///The type of the arc lengths.
76 76
    typedef typename LEN::Value Value;
77 77

	
78 78
    /// Operation traits for %Dijkstra algorithm.
79 79

	
80 80
    /// This class defines the operations that are used in the algorithm.
81 81
    /// \see DijkstraDefaultOperationTraits
82 82
    typedef DijkstraDefaultOperationTraits<Value> OperationTraits;
83 83

	
84 84
    /// The cross reference type used by the heap.
85 85

	
86 86
    /// The cross reference type used by the heap.
87 87
    /// Usually it is \c Digraph::NodeMap<int>.
88 88
    typedef typename Digraph::template NodeMap<int> HeapCrossRef;
89 89
    ///Instantiates a \c HeapCrossRef.
90 90

	
91 91
    ///This function instantiates a \ref HeapCrossRef.
92 92
    /// \param g is the digraph, to which we would like to define the
93 93
    /// \ref HeapCrossRef.
94 94
    static HeapCrossRef *createHeapCrossRef(const Digraph &g)
95 95
    {
96 96
      return new HeapCrossRef(g);
97 97
    }
98 98

	
99 99
    ///The heap type used by the %Dijkstra algorithm.
100 100

	
101 101
    ///The heap type used by the Dijkstra algorithm.
102 102
    ///
103 103
    ///\sa BinHeap
104 104
    ///\sa Dijkstra
105 105
    typedef BinHeap<typename LEN::Value, HeapCrossRef, std::less<Value> > Heap;
106 106
    ///Instantiates a \c Heap.
107 107

	
108 108
    ///This function instantiates a \ref Heap.
109 109
    static Heap *createHeap(HeapCrossRef& r)
110 110
    {
111 111
      return new Heap(r);
112 112
    }
113 113

	
114 114
    ///\brief The type of the map that stores the predecessor
115 115
    ///arcs of the shortest paths.
116 116
    ///
117 117
    ///The type of the map that stores the predecessor
118 118
    ///arcs of the shortest paths.
119
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
119
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
120 120
    typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap;
121 121
    ///Instantiates a \c PredMap.
122 122

	
123 123
    ///This function instantiates a \ref PredMap.
124 124
    ///\param g is the digraph, to which we would like to define the
125 125
    ///\ref PredMap.
126 126
    static PredMap *createPredMap(const Digraph &g)
127 127
    {
128 128
      return new PredMap(g);
129 129
    }
130 130

	
131 131
    ///The type of the map that indicates which nodes are processed.
132 132

	
133 133
    ///The type of the map that indicates which nodes are processed.
134
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
134
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
135 135
    ///By default it is a NullMap.
136 136
    typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
137 137
    ///Instantiates a \c ProcessedMap.
138 138

	
139 139
    ///This function instantiates a \ref ProcessedMap.
140 140
    ///\param g is the digraph, to which
141 141
    ///we would like to define the \ref ProcessedMap.
142 142
#ifdef DOXYGEN
143 143
    static ProcessedMap *createProcessedMap(const Digraph &g)
144 144
#else
145 145
    static ProcessedMap *createProcessedMap(const Digraph &)
146 146
#endif
147 147
    {
148 148
      return new ProcessedMap();
149 149
    }
150 150

	
151 151
    ///The type of the map that stores the distances of the nodes.
152 152

	
153 153
    ///The type of the map that stores the distances of the nodes.
154
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
154
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
155 155
    typedef typename Digraph::template NodeMap<typename LEN::Value> DistMap;
156 156
    ///Instantiates a \c DistMap.
157 157

	
158 158
    ///This function instantiates a \ref DistMap.
159 159
    ///\param g is the digraph, to which we would like to define
160 160
    ///the \ref DistMap.
161 161
    static DistMap *createDistMap(const Digraph &g)
162 162
    {
163 163
      return new DistMap(g);
164 164
    }
165 165
  };
166 166

	
167 167
  ///%Dijkstra algorithm class.
168 168

	
169 169
  /// \ingroup shortest_path
170 170
  ///This class provides an efficient implementation of the %Dijkstra algorithm.
171 171
  ///
172
  ///The %Dijkstra algorithm solves the single-source shortest path problem
173
  ///when all arc lengths are non-negative. If there are negative lengths,
174
  ///the BellmanFord algorithm should be used instead.
175
  ///
172 176
  ///The arc lengths are passed to the algorithm using a
173 177
  ///\ref concepts::ReadMap "ReadMap",
174 178
  ///so it is easy to change it to any kind of length.
175 179
  ///The type of the length is determined by the
176 180
  ///\ref concepts::ReadMap::Value "Value" of the length map.
177 181
  ///It is also possible to change the underlying priority heap.
178 182
  ///
179 183
  ///There is also a \ref dijkstra() "function-type interface" for the
180 184
  ///%Dijkstra algorithm, which is convenient in the simplier cases and
181 185
  ///it can be used easier.
182 186
  ///
183 187
  ///\tparam GR The type of the digraph the algorithm runs on.
184 188
  ///The default type is \ref ListDigraph.
185 189
  ///\tparam LEN A \ref concepts::ReadMap "readable" arc map that specifies
186 190
  ///the lengths of the arcs.
187 191
  ///It is read once for each arc, so the map may involve in
188 192
  ///relatively time consuming process to compute the arc lengths if
189 193
  ///it is necessary. The default map type is \ref
190 194
  ///concepts::Digraph::ArcMap "GR::ArcMap<int>".
191 195
#ifdef DOXYGEN
192 196
  template <typename GR, typename LEN, typename TR>
193 197
#else
194 198
  template <typename GR=ListDigraph,
195 199
            typename LEN=typename GR::template ArcMap<int>,
196 200
            typename TR=DijkstraDefaultTraits<GR,LEN> >
197 201
#endif
198 202
  class Dijkstra {
199 203
  public:
200 204

	
201 205
    ///The type of the digraph the algorithm runs on.
202 206
    typedef typename TR::Digraph Digraph;
203 207

	
204
    ///The type of the length of the arcs.
208
    ///The type of the arc lengths.
205 209
    typedef typename TR::LengthMap::Value Value;
206 210
    ///The type of the map that stores the arc lengths.
207 211
    typedef typename TR::LengthMap LengthMap;
208 212
    ///\brief The type of the map that stores the predecessor arcs of the
209 213
    ///shortest paths.
210 214
    typedef typename TR::PredMap PredMap;
211 215
    ///The type of the map that stores the distances of the nodes.
212 216
    typedef typename TR::DistMap DistMap;
213 217
    ///The type of the map that indicates which nodes are processed.
214 218
    typedef typename TR::ProcessedMap ProcessedMap;
215 219
    ///The type of the paths.
216 220
    typedef PredMapPath<Digraph, PredMap> Path;
217 221
    ///The cross reference type used for the current heap.
218 222
    typedef typename TR::HeapCrossRef HeapCrossRef;
219 223
    ///The heap type used by the algorithm.
220 224
    typedef typename TR::Heap Heap;
221 225
    ///\brief The \ref DijkstraDefaultOperationTraits "operation traits class"
222 226
    ///of the algorithm.
223 227
    typedef typename TR::OperationTraits OperationTraits;
224 228

	
225 229
    ///The \ref DijkstraDefaultTraits "traits class" of the algorithm.
226 230
    typedef TR Traits;
227 231

	
228 232
  private:
229 233

	
230 234
    typedef typename Digraph::Node Node;
231 235
    typedef typename Digraph::NodeIt NodeIt;
232 236
    typedef typename Digraph::Arc Arc;
233 237
    typedef typename Digraph::OutArcIt OutArcIt;
234 238

	
235 239
    //Pointer to the underlying digraph.
236 240
    const Digraph *G;
237 241
    //Pointer to the length map.
238 242
    const LengthMap *_length;
239 243
    //Pointer to the map of predecessors arcs.
240 244
    PredMap *_pred;
241 245
    //Indicates if _pred is locally allocated (true) or not.
242 246
    bool local_pred;
243 247
    //Pointer to the map of distances.
244 248
    DistMap *_dist;
245 249
    //Indicates if _dist is locally allocated (true) or not.
246 250
    bool local_dist;
247 251
    //Pointer to the map of processed status of the nodes.
248 252
    ProcessedMap *_processed;
249 253
    //Indicates if _processed is locally allocated (true) or not.
250 254
    bool local_processed;
251 255
    //Pointer to the heap cross references.
252 256
    HeapCrossRef *_heap_cross_ref;
253 257
    //Indicates if _heap_cross_ref is locally allocated (true) or not.
254 258
    bool local_heap_cross_ref;
255 259
    //Pointer to the heap.
256 260
    Heap *_heap;
257 261
    //Indicates if _heap is locally allocated (true) or not.
258 262
    bool local_heap;
259 263

	
260 264
    //Creates the maps if necessary.
261 265
    void create_maps()
262 266
    {
263 267
      if(!_pred) {
264 268
        local_pred = true;
265 269
        _pred = Traits::createPredMap(*G);
266 270
      }
267 271
      if(!_dist) {
268 272
        local_dist = true;
269 273
        _dist = Traits::createDistMap(*G);
270 274
      }
271 275
      if(!_processed) {
272 276
        local_processed = true;
273 277
        _processed = Traits::createProcessedMap(*G);
274 278
      }
275 279
      if (!_heap_cross_ref) {
276 280
        local_heap_cross_ref = true;
277 281
        _heap_cross_ref = Traits::createHeapCrossRef(*G);
278 282
      }
279 283
      if (!_heap) {
280 284
        local_heap = true;
281 285
        _heap = Traits::createHeap(*_heap_cross_ref);
282 286
      }
283 287
    }
284 288

	
285 289
  public:
286 290

	
287 291
    typedef Dijkstra Create;
288 292

	
289 293
    ///\name Named Template Parameters
290 294

	
291 295
    ///@{
292 296

	
293 297
    template <class T>
294 298
    struct SetPredMapTraits : public Traits {
295 299
      typedef T PredMap;
296 300
      static PredMap *createPredMap(const Digraph &)
297 301
      {
298 302
        LEMON_ASSERT(false, "PredMap is not initialized");
299 303
        return 0; // ignore warnings
300 304
      }
301 305
    };
302 306
    ///\brief \ref named-templ-param "Named parameter" for setting
303 307
    ///\c PredMap type.
304 308
    ///
305 309
    ///\ref named-templ-param "Named parameter" for setting
306 310
    ///\c PredMap type.
307
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
311
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
308 312
    template <class T>
309 313
    struct SetPredMap
310 314
      : public Dijkstra< Digraph, LengthMap, SetPredMapTraits<T> > {
311 315
      typedef Dijkstra< Digraph, LengthMap, SetPredMapTraits<T> > Create;
312 316
    };
313 317

	
314 318
    template <class T>
315 319
    struct SetDistMapTraits : public Traits {
316 320
      typedef T DistMap;
317 321
      static DistMap *createDistMap(const Digraph &)
318 322
      {
319 323
        LEMON_ASSERT(false, "DistMap is not initialized");
320 324
        return 0; // ignore warnings
321 325
      }
322 326
    };
323 327
    ///\brief \ref named-templ-param "Named parameter" for setting
324 328
    ///\c DistMap type.
325 329
    ///
326 330
    ///\ref named-templ-param "Named parameter" for setting
327 331
    ///\c DistMap type.
328
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
332
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
329 333
    template <class T>
330 334
    struct SetDistMap
331 335
      : public Dijkstra< Digraph, LengthMap, SetDistMapTraits<T> > {
332 336
      typedef Dijkstra< Digraph, LengthMap, SetDistMapTraits<T> > Create;
333 337
    };
334 338

	
335 339
    template <class T>
336 340
    struct SetProcessedMapTraits : public Traits {
337 341
      typedef T ProcessedMap;
338 342
      static ProcessedMap *createProcessedMap(const Digraph &)
339 343
      {
340 344
        LEMON_ASSERT(false, "ProcessedMap is not initialized");
341 345
        return 0; // ignore warnings
342 346
      }
343 347
    };
344 348
    ///\brief \ref named-templ-param "Named parameter" for setting
345 349
    ///\c ProcessedMap type.
346 350
    ///
347 351
    ///\ref named-templ-param "Named parameter" for setting
348 352
    ///\c ProcessedMap type.
349
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
353
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
350 354
    template <class T>
351 355
    struct SetProcessedMap
352 356
      : public Dijkstra< Digraph, LengthMap, SetProcessedMapTraits<T> > {
353 357
      typedef Dijkstra< Digraph, LengthMap, SetProcessedMapTraits<T> > Create;
354 358
    };
355 359

	
356 360
    struct SetStandardProcessedMapTraits : public Traits {
357 361
      typedef typename Digraph::template NodeMap<bool> ProcessedMap;
358 362
      static ProcessedMap *createProcessedMap(const Digraph &g)
359 363
      {
360 364
        return new ProcessedMap(g);
361 365
      }
362 366
    };
363 367
    ///\brief \ref named-templ-param "Named parameter" for setting
364 368
    ///\c ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>.
365 369
    ///
366 370
    ///\ref named-templ-param "Named parameter" for setting
367 371
    ///\c ProcessedMap type to be <tt>Digraph::NodeMap<bool></tt>.
368 372
    ///If you don't set it explicitly, it will be automatically allocated.
369 373
    struct SetStandardProcessedMap
370 374
      : public Dijkstra< Digraph, LengthMap, SetStandardProcessedMapTraits > {
371 375
      typedef Dijkstra< Digraph, LengthMap, SetStandardProcessedMapTraits >
372 376
      Create;
373 377
    };
374 378

	
375 379
    template <class H, class CR>
376 380
    struct SetHeapTraits : public Traits {
377 381
      typedef CR HeapCrossRef;
378 382
      typedef H Heap;
379 383
      static HeapCrossRef *createHeapCrossRef(const Digraph &) {
380 384
        LEMON_ASSERT(false, "HeapCrossRef is not initialized");
381 385
        return 0; // ignore warnings
382 386
      }
383 387
      static Heap *createHeap(HeapCrossRef &)
384 388
      {
385 389
        LEMON_ASSERT(false, "Heap is not initialized");
386 390
        return 0; // ignore warnings
387 391
      }
388 392
    };
389 393
    ///\brief \ref named-templ-param "Named parameter" for setting
390 394
    ///heap and cross reference types
391 395
    ///
392 396
    ///\ref named-templ-param "Named parameter" for setting heap and cross
393 397
    ///reference types. If this named parameter is used, then external
394 398
    ///heap and cross reference objects must be passed to the algorithm
395 399
    ///using the \ref heap() function before calling \ref run(Node) "run()"
396 400
    ///or \ref init().
397 401
    ///\sa SetStandardHeap
398 402
    template <class H, class CR = typename Digraph::template NodeMap<int> >
399 403
    struct SetHeap
400 404
      : public Dijkstra< Digraph, LengthMap, SetHeapTraits<H, CR> > {
401 405
      typedef Dijkstra< Digraph, LengthMap, SetHeapTraits<H, CR> > Create;
402 406
    };
403 407

	
404 408
    template <class H, class CR>
405 409
    struct SetStandardHeapTraits : public Traits {
406 410
      typedef CR HeapCrossRef;
407 411
      typedef H Heap;
408 412
      static HeapCrossRef *createHeapCrossRef(const Digraph &G) {
409 413
        return new HeapCrossRef(G);
410 414
      }
411 415
      static Heap *createHeap(HeapCrossRef &R)
412 416
      {
413 417
        return new Heap(R);
414 418
      }
415 419
    };
416 420
    ///\brief \ref named-templ-param "Named parameter" for setting
417 421
    ///heap and cross reference types with automatic allocation
418 422
    ///
419 423
    ///\ref named-templ-param "Named parameter" for setting heap and cross
420 424
    ///reference types with automatic allocation.
421 425
    ///They should have standard constructor interfaces to be able to
422 426
    ///automatically created by the algorithm (i.e. the digraph should be
423 427
    ///passed to the constructor of the cross reference and the cross
424 428
    ///reference should be passed to the constructor of the heap).
425 429
    ///However external heap and cross reference objects could also be
426 430
    ///passed to the algorithm using the \ref heap() function before
427 431
    ///calling \ref run(Node) "run()" or \ref init().
428 432
    ///\sa SetHeap
429 433
    template <class H, class CR = typename Digraph::template NodeMap<int> >
430 434
    struct SetStandardHeap
431 435
      : public Dijkstra< Digraph, LengthMap, SetStandardHeapTraits<H, CR> > {
432 436
      typedef Dijkstra< Digraph, LengthMap, SetStandardHeapTraits<H, CR> >
433 437
      Create;
434 438
    };
435 439

	
436 440
    template <class T>
437 441
    struct SetOperationTraitsTraits : public Traits {
438 442
      typedef T OperationTraits;
439 443
    };
440 444

	
441 445
    /// \brief \ref named-templ-param "Named parameter" for setting
442 446
    ///\c OperationTraits type
443 447
    ///
444 448
    ///\ref named-templ-param "Named parameter" for setting
445 449
    ///\c OperationTraits type.
450
    /// For more information see \ref DijkstraDefaultOperationTraits.
446 451
    template <class T>
447 452
    struct SetOperationTraits
448 453
      : public Dijkstra<Digraph, LengthMap, SetOperationTraitsTraits<T> > {
449 454
      typedef Dijkstra<Digraph, LengthMap, SetOperationTraitsTraits<T> >
450 455
      Create;
451 456
    };
452 457

	
453 458
    ///@}
454 459

	
455 460
  protected:
456 461

	
457 462
    Dijkstra() {}
458 463

	
459 464
  public:
460 465

	
461 466
    ///Constructor.
462 467

	
463 468
    ///Constructor.
464 469
    ///\param g The digraph the algorithm runs on.
465 470
    ///\param length The length map used by the algorithm.
466 471
    Dijkstra(const Digraph& g, const LengthMap& length) :
467 472
      G(&g), _length(&length),
468 473
      _pred(NULL), local_pred(false),
469 474
      _dist(NULL), local_dist(false),
470 475
      _processed(NULL), local_processed(false),
471 476
      _heap_cross_ref(NULL), local_heap_cross_ref(false),
472 477
      _heap(NULL), local_heap(false)
473 478
    { }
474 479

	
475 480
    ///Destructor.
476 481
    ~Dijkstra()
477 482
    {
478 483
      if(local_pred) delete _pred;
479 484
      if(local_dist) delete _dist;
480 485
      if(local_processed) delete _processed;
481 486
      if(local_heap_cross_ref) delete _heap_cross_ref;
482 487
      if(local_heap) delete _heap;
483 488
    }
484 489

	
485 490
    ///Sets the length map.
486 491

	
487 492
    ///Sets the length map.
488 493
    ///\return <tt> (*this) </tt>
489 494
    Dijkstra &lengthMap(const LengthMap &m)
490 495
    {
491 496
      _length = &m;
492 497
      return *this;
493 498
    }
494 499

	
495 500
    ///Sets the map that stores the predecessor arcs.
496 501

	
497 502
    ///Sets the map that stores the predecessor arcs.
498 503
    ///If you don't use this function before calling \ref run(Node) "run()"
499 504
    ///or \ref init(), an instance will be allocated automatically.
500 505
    ///The destructor deallocates this automatically allocated map,
501 506
    ///of course.
502 507
    ///\return <tt> (*this) </tt>
503 508
    Dijkstra &predMap(PredMap &m)
504 509
    {
505 510
      if(local_pred) {
506 511
        delete _pred;
507 512
        local_pred=false;
508 513
      }
509 514
      _pred = &m;
510 515
      return *this;
511 516
    }
512 517

	
513 518
    ///Sets the map that indicates which nodes are processed.
514 519

	
515 520
    ///Sets the map that indicates which nodes are processed.
516 521
    ///If you don't use this function before calling \ref run(Node) "run()"
517 522
    ///or \ref init(), an instance will be allocated automatically.
518 523
    ///The destructor deallocates this automatically allocated map,
519 524
    ///of course.
520 525
    ///\return <tt> (*this) </tt>
521 526
    Dijkstra &processedMap(ProcessedMap &m)
522 527
    {
523 528
      if(local_processed) {
524 529
        delete _processed;
525 530
        local_processed=false;
526 531
      }
527 532
      _processed = &m;
528 533
      return *this;
529 534
    }
530 535

	
531 536
    ///Sets the map that stores the distances of the nodes.
532 537

	
533 538
    ///Sets the map that stores the distances of the nodes calculated by the
534 539
    ///algorithm.
535 540
    ///If you don't use this function before calling \ref run(Node) "run()"
536 541
    ///or \ref init(), an instance will be allocated automatically.
537 542
    ///The destructor deallocates this automatically allocated map,
538 543
    ///of course.
539 544
    ///\return <tt> (*this) </tt>
540 545
    Dijkstra &distMap(DistMap &m)
541 546
    {
542 547
      if(local_dist) {
543 548
        delete _dist;
544 549
        local_dist=false;
545 550
      }
546 551
      _dist = &m;
547 552
      return *this;
548 553
    }
549 554

	
550 555
    ///Sets the heap and the cross reference used by algorithm.
551 556

	
552 557
    ///Sets the heap and the cross reference used by algorithm.
553 558
    ///If you don't use this function before calling \ref run(Node) "run()"
554 559
    ///or \ref init(), heap and cross reference instances will be
555 560
    ///allocated automatically.
556 561
    ///The destructor deallocates these automatically allocated objects,
557 562
    ///of course.
558 563
    ///\return <tt> (*this) </tt>
559 564
    Dijkstra &heap(Heap& hp, HeapCrossRef &cr)
560 565
    {
561 566
      if(local_heap_cross_ref) {
562 567
        delete _heap_cross_ref;
563 568
        local_heap_cross_ref=false;
564 569
      }
565 570
      _heap_cross_ref = &cr;
566 571
      if(local_heap) {
567 572
        delete _heap;
568 573
        local_heap=false;
569 574
      }
570 575
      _heap = &hp;
571 576
      return *this;
572 577
    }
573 578

	
574 579
  private:
575 580

	
576 581
    void finalizeNodeData(Node v,Value dst)
577 582
    {
578 583
      _processed->set(v,true);
579 584
      _dist->set(v, dst);
580 585
    }
581 586

	
582 587
  public:
583 588

	
584 589
    ///\name Execution Control
585 590
    ///The simplest way to execute the %Dijkstra algorithm is to use
586 591
    ///one of the member functions called \ref run(Node) "run()".\n
587
    ///If you need more control on the execution, first you have to call
588
    ///\ref init(), then you can add several source nodes with
592
    ///If you need better control on the execution, you have to call
593
    ///\ref init() first, then you can add several source nodes with
589 594
    ///\ref addSource(). Finally the actual path computation can be
590 595
    ///performed with one of the \ref start() functions.
591 596

	
592 597
    ///@{
593 598

	
594 599
    ///\brief Initializes the internal data structures.
595 600
    ///
596 601
    ///Initializes the internal data structures.
597 602
    void init()
598 603
    {
599 604
      create_maps();
600 605
      _heap->clear();
601 606
      for ( NodeIt u(*G) ; u!=INVALID ; ++u ) {
602 607
        _pred->set(u,INVALID);
603 608
        _processed->set(u,false);
604 609
        _heap_cross_ref->set(u,Heap::PRE_HEAP);
605 610
      }
606 611
    }
607 612

	
608 613
    ///Adds a new source node.
609 614

	
610 615
    ///Adds a new source node to the priority heap.
611 616
    ///The optional second parameter is the initial distance of the node.
612 617
    ///
613 618
    ///The function checks if the node has already been added to the heap and
614 619
    ///it is pushed to the heap only if either it was not in the heap
615 620
    ///or the shortest path found till then is shorter than \c dst.
616 621
    void addSource(Node s,Value dst=OperationTraits::zero())
617 622
    {
618 623
      if(_heap->state(s) != Heap::IN_HEAP) {
619 624
        _heap->push(s,dst);
620 625
      } else if(OperationTraits::less((*_heap)[s], dst)) {
621 626
        _heap->set(s,dst);
622 627
        _pred->set(s,INVALID);
623 628
      }
624 629
    }
625 630

	
626 631
    ///Processes the next node in the priority heap
627 632

	
628 633
    ///Processes the next node in the priority heap.
629 634
    ///
630 635
    ///\return The processed node.
631 636
    ///
632 637
    ///\warning The priority heap must not be empty.
633 638
    Node processNextNode()
634 639
    {
635 640
      Node v=_heap->top();
636 641
      Value oldvalue=_heap->prio();
637 642
      _heap->pop();
638 643
      finalizeNodeData(v,oldvalue);
639 644

	
640 645
      for(OutArcIt e(*G,v); e!=INVALID; ++e) {
641 646
        Node w=G->target(e);
642 647
        switch(_heap->state(w)) {
643 648
        case Heap::PRE_HEAP:
644 649
          _heap->push(w,OperationTraits::plus(oldvalue, (*_length)[e]));
645 650
          _pred->set(w,e);
646 651
          break;
647 652
        case Heap::IN_HEAP:
648 653
          {
649 654
            Value newvalue = OperationTraits::plus(oldvalue, (*_length)[e]);
650 655
            if ( OperationTraits::less(newvalue, (*_heap)[w]) ) {
651 656
              _heap->decrease(w, newvalue);
652 657
              _pred->set(w,e);
653 658
            }
654 659
          }
655 660
          break;
656 661
        case Heap::POST_HEAP:
657 662
          break;
658 663
        }
659 664
      }
660 665
      return v;
661 666
    }
662 667

	
663 668
    ///The next node to be processed.
664 669

	
665 670
    ///Returns the next node to be processed or \c INVALID if the
666 671
    ///priority heap is empty.
667 672
    Node nextNode() const
668 673
    {
669 674
      return !_heap->empty()?_heap->top():INVALID;
670 675
    }
671 676

	
672 677
    ///Returns \c false if there are nodes to be processed.
673 678

	
674 679
    ///Returns \c false if there are nodes to be processed
675 680
    ///in the priority heap.
676 681
    bool emptyQueue() const { return _heap->empty(); }
677 682

	
678 683
    ///Returns the number of the nodes to be processed.
679 684

	
680 685
    ///Returns the number of the nodes to be processed
681 686
    ///in the priority heap.
682 687
    int queueSize() const { return _heap->size(); }
683 688

	
684 689
    ///Executes the algorithm.
685 690

	
686 691
    ///Executes the algorithm.
687 692
    ///
688 693
    ///This method runs the %Dijkstra algorithm from the root node(s)
689 694
    ///in order to compute the shortest path to each node.
690 695
    ///
691 696
    ///The algorithm computes
692 697
    ///- the shortest path tree (forest),
693 698
    ///- the distance of each node from the root(s).
694 699
    ///
695 700
    ///\pre init() must be called and at least one root node should be
696 701
    ///added with addSource() before using this function.
697 702
    ///
698 703
    ///\note <tt>d.start()</tt> is just a shortcut of the following code.
699 704
    ///\code
700 705
    ///  while ( !d.emptyQueue() ) {
701 706
    ///    d.processNextNode();
702 707
    ///  }
703 708
    ///\endcode
704 709
    void start()
705 710
    {
706 711
      while ( !emptyQueue() ) processNextNode();
707 712
    }
708 713

	
709 714
    ///Executes the algorithm until the given target node is processed.
710 715

	
711 716
    ///Executes the algorithm until the given target node is processed.
712 717
    ///
713 718
    ///This method runs the %Dijkstra algorithm from the root node(s)
714 719
    ///in order to compute the shortest path to \c t.
715 720
    ///
716 721
    ///The algorithm computes
717 722
    ///- the shortest path to \c t,
718 723
    ///- the distance of \c t from the root(s).
719 724
    ///
720 725
    ///\pre init() must be called and at least one root node should be
721 726
    ///added with addSource() before using this function.
722 727
    void start(Node t)
723 728
    {
724 729
      while ( !_heap->empty() && _heap->top()!=t ) processNextNode();
725 730
      if ( !_heap->empty() ) {
726 731
        finalizeNodeData(_heap->top(),_heap->prio());
727 732
        _heap->pop();
728 733
      }
729 734
    }
730 735

	
731 736
    ///Executes the algorithm until a condition is met.
732 737

	
733 738
    ///Executes the algorithm until a condition is met.
734 739
    ///
735 740
    ///This method runs the %Dijkstra algorithm from the root node(s) in
736 741
    ///order to compute the shortest path to a node \c v with
737 742
    /// <tt>nm[v]</tt> true, if such a node can be found.
738 743
    ///
739 744
    ///\param nm A \c bool (or convertible) node map. The algorithm
740 745
    ///will stop when it reaches a node \c v with <tt>nm[v]</tt> true.
741 746
    ///
742 747
    ///\return The reached node \c v with <tt>nm[v]</tt> true or
743 748
    ///\c INVALID if no such node was found.
744 749
    ///
745 750
    ///\pre init() must be called and at least one root node should be
746 751
    ///added with addSource() before using this function.
747 752
    template<class NodeBoolMap>
748 753
    Node start(const NodeBoolMap &nm)
749 754
    {
750 755
      while ( !_heap->empty() && !nm[_heap->top()] ) processNextNode();
751 756
      if ( _heap->empty() ) return INVALID;
752 757
      finalizeNodeData(_heap->top(),_heap->prio());
753 758
      return _heap->top();
754 759
    }
755 760

	
756 761
    ///Runs the algorithm from the given source node.
757 762

	
758 763
    ///This method runs the %Dijkstra algorithm from node \c s
759 764
    ///in order to compute the shortest path to each node.
760 765
    ///
761 766
    ///The algorithm computes
762 767
    ///- the shortest path tree,
763 768
    ///- the distance of each node from the root.
764 769
    ///
765 770
    ///\note <tt>d.run(s)</tt> is just a shortcut of the following code.
766 771
    ///\code
767 772
    ///  d.init();
768 773
    ///  d.addSource(s);
769 774
    ///  d.start();
770 775
    ///\endcode
771 776
    void run(Node s) {
772 777
      init();
773 778
      addSource(s);
774 779
      start();
775 780
    }
776 781

	
777 782
    ///Finds the shortest path between \c s and \c t.
778 783

	
779 784
    ///This method runs the %Dijkstra algorithm from node \c s
780 785
    ///in order to compute the shortest path to node \c t
781 786
    ///(it stops searching when \c t is processed).
782 787
    ///
783 788
    ///\return \c true if \c t is reachable form \c s.
784 789
    ///
785 790
    ///\note Apart from the return value, <tt>d.run(s,t)</tt> is just a
786 791
    ///shortcut of the following code.
787 792
    ///\code
788 793
    ///  d.init();
789 794
    ///  d.addSource(s);
790 795
    ///  d.start(t);
791 796
    ///\endcode
792 797
    bool run(Node s,Node t) {
793 798
      init();
794 799
      addSource(s);
795 800
      start(t);
796 801
      return (*_heap_cross_ref)[t] == Heap::POST_HEAP;
797 802
    }
798 803

	
799 804
    ///@}
800 805

	
801 806
    ///\name Query Functions
802 807
    ///The results of the %Dijkstra algorithm can be obtained using these
803 808
    ///functions.\n
804
    ///Either \ref run(Node) "run()" or \ref start() should be called
809
    ///Either \ref run(Node) "run()" or \ref init() should be called
805 810
    ///before using them.
806 811

	
807 812
    ///@{
808 813

	
809
    ///The shortest path to a node.
814
    ///The shortest path to the given node.
810 815

	
811
    ///Returns the shortest path to a node.
816
    ///Returns the shortest path to the given node from the root(s).
812 817
    ///
813 818
    ///\warning \c t should be reached from the root(s).
814 819
    ///
815 820
    ///\pre Either \ref run(Node) "run()" or \ref init()
816 821
    ///must be called before using this function.
817 822
    Path path(Node t) const { return Path(*G, *_pred, t); }
818 823

	
819
    ///The distance of a node from the root(s).
824
    ///The distance of the given node from the root(s).
820 825

	
821
    ///Returns the distance of a node from the root(s).
826
    ///Returns the distance of the given node from the root(s).
822 827
    ///
823 828
    ///\warning If node \c v is not reached from the root(s), then
824 829
    ///the return value of this function is undefined.
825 830
    ///
826 831
    ///\pre Either \ref run(Node) "run()" or \ref init()
827 832
    ///must be called before using this function.
828 833
    Value dist(Node v) const { return (*_dist)[v]; }
829 834

	
830
    ///Returns the 'previous arc' of the shortest path tree for a node.
831

	
835
    ///\brief Returns the 'previous arc' of the shortest path tree for
836
    ///the given node.
837
    ///
832 838
    ///This function returns the 'previous arc' of the shortest path
833 839
    ///tree for the node \c v, i.e. it returns the last arc of a
834 840
    ///shortest path from a root to \c v. It is \c INVALID if \c v
835 841
    ///is not reached from the root(s) or if \c v is a root.
836 842
    ///
837 843
    ///The shortest path tree used here is equal to the shortest path
838
    ///tree used in \ref predNode().
844
    ///tree used in \ref predNode() and \ref predMap().
839 845
    ///
840 846
    ///\pre Either \ref run(Node) "run()" or \ref init()
841 847
    ///must be called before using this function.
842 848
    Arc predArc(Node v) const { return (*_pred)[v]; }
843 849

	
844
    ///Returns the 'previous node' of the shortest path tree for a node.
845

	
850
    ///\brief Returns the 'previous node' of the shortest path tree for
851
    ///the given node.
852
    ///
846 853
    ///This function returns the 'previous node' of the shortest path
847 854
    ///tree for the node \c v, i.e. it returns the last but one node
848
    ///from a shortest path from a root to \c v. It is \c INVALID
855
    ///of a shortest path from a root to \c v. It is \c INVALID
849 856
    ///if \c v is not reached from the root(s) or if \c v is a root.
850 857
    ///
851 858
    ///The shortest path tree used here is equal to the shortest path
852
    ///tree used in \ref predArc().
859
    ///tree used in \ref predArc() and \ref predMap().
853 860
    ///
854 861
    ///\pre Either \ref run(Node) "run()" or \ref init()
855 862
    ///must be called before using this function.
856 863
    Node predNode(Node v) const { return (*_pred)[v]==INVALID ? INVALID:
857 864
                                  G->source((*_pred)[v]); }
858 865

	
859 866
    ///\brief Returns a const reference to the node map that stores the
860 867
    ///distances of the nodes.
861 868
    ///
862 869
    ///Returns a const reference to the node map that stores the distances
863 870
    ///of the nodes calculated by the algorithm.
864 871
    ///
865 872
    ///\pre Either \ref run(Node) "run()" or \ref init()
866 873
    ///must be called before using this function.
867 874
    const DistMap &distMap() const { return *_dist;}
868 875

	
869 876
    ///\brief Returns a const reference to the node map that stores the
870 877
    ///predecessor arcs.
871 878
    ///
872 879
    ///Returns a const reference to the node map that stores the predecessor
873
    ///arcs, which form the shortest path tree.
880
    ///arcs, which form the shortest path tree (forest).
874 881
    ///
875 882
    ///\pre Either \ref run(Node) "run()" or \ref init()
876 883
    ///must be called before using this function.
877 884
    const PredMap &predMap() const { return *_pred;}
878 885

	
879
    ///Checks if a node is reached from the root(s).
886
    ///Checks if the given node is reached from the root(s).
880 887

	
881 888
    ///Returns \c true if \c v is reached from the root(s).
882 889
    ///
883 890
    ///\pre Either \ref run(Node) "run()" or \ref init()
884 891
    ///must be called before using this function.
885 892
    bool reached(Node v) const { return (*_heap_cross_ref)[v] !=
886 893
                                        Heap::PRE_HEAP; }
887 894

	
888 895
    ///Checks if a node is processed.
889 896

	
890 897
    ///Returns \c true if \c v is processed, i.e. the shortest
891 898
    ///path to \c v has already found.
892 899
    ///
893 900
    ///\pre Either \ref run(Node) "run()" or \ref init()
894 901
    ///must be called before using this function.
895 902
    bool processed(Node v) const { return (*_heap_cross_ref)[v] ==
896 903
                                          Heap::POST_HEAP; }
897 904

	
898
    ///The current distance of a node from the root(s).
905
    ///The current distance of the given node from the root(s).
899 906

	
900
    ///Returns the current distance of a node from the root(s).
907
    ///Returns the current distance of the given node from the root(s).
901 908
    ///It may be decreased in the following processes.
902 909
    ///
903 910
    ///\pre Either \ref run(Node) "run()" or \ref init()
904 911
    ///must be called before using this function and
905 912
    ///node \c v must be reached but not necessarily processed.
906 913
    Value currentDist(Node v) const {
907 914
      return processed(v) ? (*_dist)[v] : (*_heap)[v];
908 915
    }
909 916

	
910 917
    ///@}
911 918
  };
912 919

	
913 920

	
914 921
  ///Default traits class of dijkstra() function.
915 922

	
916 923
  ///Default traits class of dijkstra() function.
917 924
  ///\tparam GR The type of the digraph.
918 925
  ///\tparam LEN The type of the length map.
919 926
  template<class GR, class LEN>
920 927
  struct DijkstraWizardDefaultTraits
921 928
  {
922 929
    ///The type of the digraph the algorithm runs on.
923 930
    typedef GR Digraph;
924 931
    ///The type of the map that stores the arc lengths.
925 932

	
926 933
    ///The type of the map that stores the arc lengths.
927
    ///It must meet the \ref concepts::ReadMap "ReadMap" concept.
934
    ///It must conform to the \ref concepts::ReadMap "ReadMap" concept.
928 935
    typedef LEN LengthMap;
929
    ///The type of the length of the arcs.
936
    ///The type of the arc lengths.
930 937
    typedef typename LEN::Value Value;
931 938

	
932 939
    /// Operation traits for Dijkstra algorithm.
933 940

	
934 941
    /// This class defines the operations that are used in the algorithm.
935 942
    /// \see DijkstraDefaultOperationTraits
936 943
    typedef DijkstraDefaultOperationTraits<Value> OperationTraits;
937 944

	
938 945
    /// The cross reference type used by the heap.
939 946

	
940 947
    /// The cross reference type used by the heap.
941 948
    /// Usually it is \c Digraph::NodeMap<int>.
942 949
    typedef typename Digraph::template NodeMap<int> HeapCrossRef;
943 950
    ///Instantiates a \ref HeapCrossRef.
944 951

	
945 952
    ///This function instantiates a \ref HeapCrossRef.
946 953
    /// \param g is the digraph, to which we would like to define the
947 954
    /// HeapCrossRef.
948 955
    static HeapCrossRef *createHeapCrossRef(const Digraph &g)
949 956
    {
950 957
      return new HeapCrossRef(g);
951 958
    }
952 959

	
953 960
    ///The heap type used by the Dijkstra algorithm.
954 961

	
955 962
    ///The heap type used by the Dijkstra algorithm.
956 963
    ///
957 964
    ///\sa BinHeap
958 965
    ///\sa Dijkstra
959 966
    typedef BinHeap<Value, typename Digraph::template NodeMap<int>,
960 967
                    std::less<Value> > Heap;
961 968

	
962 969
    ///Instantiates a \ref Heap.
963 970

	
964 971
    ///This function instantiates a \ref Heap.
965 972
    /// \param r is the HeapCrossRef which is used.
966 973
    static Heap *createHeap(HeapCrossRef& r)
967 974
    {
968 975
      return new Heap(r);
969 976
    }
970 977

	
971 978
    ///\brief The type of the map that stores the predecessor
972 979
    ///arcs of the shortest paths.
973 980
    ///
974 981
    ///The type of the map that stores the predecessor
975 982
    ///arcs of the shortest paths.
976
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
983
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
977 984
    typedef typename Digraph::template NodeMap<typename Digraph::Arc> PredMap;
978 985
    ///Instantiates a PredMap.
979 986

	
980 987
    ///This function instantiates a PredMap.
981 988
    ///\param g is the digraph, to which we would like to define the
982 989
    ///PredMap.
983 990
    static PredMap *createPredMap(const Digraph &g)
984 991
    {
985 992
      return new PredMap(g);
986 993
    }
987 994

	
988 995
    ///The type of the map that indicates which nodes are processed.
989 996

	
990 997
    ///The type of the map that indicates which nodes are processed.
991
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
998
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
992 999
    ///By default it is a NullMap.
993 1000
    typedef NullMap<typename Digraph::Node,bool> ProcessedMap;
994 1001
    ///Instantiates a ProcessedMap.
995 1002

	
996 1003
    ///This function instantiates a ProcessedMap.
997 1004
    ///\param g is the digraph, to which
998 1005
    ///we would like to define the ProcessedMap.
999 1006
#ifdef DOXYGEN
1000 1007
    static ProcessedMap *createProcessedMap(const Digraph &g)
1001 1008
#else
1002 1009
    static ProcessedMap *createProcessedMap(const Digraph &)
1003 1010
#endif
1004 1011
    {
1005 1012
      return new ProcessedMap();
1006 1013
    }
1007 1014

	
1008 1015
    ///The type of the map that stores the distances of the nodes.
1009 1016

	
1010 1017
    ///The type of the map that stores the distances of the nodes.
1011
    ///It must meet the \ref concepts::WriteMap "WriteMap" concept.
1018
    ///It must conform to the \ref concepts::WriteMap "WriteMap" concept.
1012 1019
    typedef typename Digraph::template NodeMap<typename LEN::Value> DistMap;
1013 1020
    ///Instantiates a DistMap.
1014 1021

	
1015 1022
    ///This function instantiates a DistMap.
1016 1023
    ///\param g is the digraph, to which we would like to define
1017 1024
    ///the DistMap
1018 1025
    static DistMap *createDistMap(const Digraph &g)
1019 1026
    {
1020 1027
      return new DistMap(g);
1021 1028
    }
1022 1029

	
1023 1030
    ///The type of the shortest paths.
1024 1031

	
1025 1032
    ///The type of the shortest paths.
1026
    ///It must meet the \ref concepts::Path "Path" concept.
1033
    ///It must conform to the \ref concepts::Path "Path" concept.
1027 1034
    typedef lemon::Path<Digraph> Path;
1028 1035
  };
1029 1036

	
1030 1037
  /// Default traits class used by DijkstraWizard
1031 1038

	
1032
  /// To make it easier to use Dijkstra algorithm
1033
  /// we have created a wizard class.
1034
  /// This \ref DijkstraWizard class needs default traits,
1035
  /// as well as the \ref Dijkstra class.
1036
  /// The \ref DijkstraWizardBase is a class to be the default traits of the
1037
  /// \ref DijkstraWizard class.
1039
  /// Default traits class used by DijkstraWizard.
1040
  /// \tparam GR The type of the digraph.
1041
  /// \tparam LEN The type of the length map.
1038 1042
  template<typename GR, typename LEN>
1039 1043
  class DijkstraWizardBase : public DijkstraWizardDefaultTraits<GR,LEN>
1040 1044
  {
1041 1045
    typedef DijkstraWizardDefaultTraits<GR,LEN> Base;
1042 1046
  protected:
1043 1047
    //The type of the nodes in the digraph.
1044 1048
    typedef typename Base::Digraph::Node Node;
1045 1049

	
1046 1050
    //Pointer to the digraph the algorithm runs on.
1047 1051
    void *_g;
1048 1052
    //Pointer to the length map.
1049 1053
    void *_length;
1050 1054
    //Pointer to the map of processed nodes.
1051 1055
    void *_processed;
1052 1056
    //Pointer to the map of predecessors arcs.
1053 1057
    void *_pred;
1054 1058
    //Pointer to the map of distances.
1055 1059
    void *_dist;
1056 1060
    //Pointer to the shortest path to the target node.
1057 1061
    void *_path;
1058 1062
    //Pointer to the distance of the target node.
1059 1063
    void *_di;
1060 1064

	
1061 1065
  public:
1062 1066
    /// Constructor.
1063 1067

	
1064 1068
    /// This constructor does not require parameters, therefore it initiates
1065 1069
    /// all of the attributes to \c 0.
1066 1070
    DijkstraWizardBase() : _g(0), _length(0), _processed(0), _pred(0),
1067 1071
                           _dist(0), _path(0), _di(0) {}
1068 1072

	
1069 1073
    /// Constructor.
1070 1074

	
1071 1075
    /// This constructor requires two parameters,
1072 1076
    /// others are initiated to \c 0.
1073 1077
    /// \param g The digraph the algorithm runs on.
1074 1078
    /// \param l The length map.
1075 1079
    DijkstraWizardBase(const GR &g,const LEN &l) :
1076 1080
      _g(reinterpret_cast<void*>(const_cast<GR*>(&g))),
1077 1081
      _length(reinterpret_cast<void*>(const_cast<LEN*>(&l))),
1078 1082
      _processed(0), _pred(0), _dist(0), _path(0), _di(0) {}
1079 1083

	
1080 1084
  };
1081 1085

	
1082 1086
  /// Auxiliary class for the function-type interface of Dijkstra algorithm.
1083 1087

	
1084 1088
  /// This auxiliary class is created to implement the
1085 1089
  /// \ref dijkstra() "function-type interface" of \ref Dijkstra algorithm.
1086 1090
  /// It does not have own \ref run(Node) "run()" method, it uses the
1087 1091
  /// functions and features of the plain \ref Dijkstra.
1088 1092
  ///
1089 1093
  /// This class should only be used through the \ref dijkstra() function,
1090 1094
  /// which makes it easier to use the algorithm.
1091 1095
  template<class TR>
1092 1096
  class DijkstraWizard : public TR
1093 1097
  {
1094 1098
    typedef TR Base;
1095 1099

	
1096
    ///The type of the digraph the algorithm runs on.
1097 1100
    typedef typename TR::Digraph Digraph;
1098 1101

	
1099 1102
    typedef typename Digraph::Node Node;
1100 1103
    typedef typename Digraph::NodeIt NodeIt;
1101 1104
    typedef typename Digraph::Arc Arc;
1102 1105
    typedef typename Digraph::OutArcIt OutArcIt;
1103 1106

	
1104
    ///The type of the map that stores the arc lengths.
1105 1107
    typedef typename TR::LengthMap LengthMap;
1106
    ///The type of the length of the arcs.
1107 1108
    typedef typename LengthMap::Value Value;
1108
    ///\brief The type of the map that stores the predecessor
1109
    ///arcs of the shortest paths.
1110 1109
    typedef typename TR::PredMap PredMap;
1111
    ///The type of the map that stores the distances of the nodes.
1112 1110
    typedef typename TR::DistMap DistMap;
1113
    ///The type of the map that indicates which nodes are processed.
1114 1111
    typedef typename TR::ProcessedMap ProcessedMap;
1115
    ///The type of the shortest paths
1116 1112
    typedef typename TR::Path Path;
1117
    ///The heap type used by the dijkstra algorithm.
1118 1113
    typedef typename TR::Heap Heap;
1119 1114

	
1120 1115
  public:
1121 1116

	
1122 1117
    /// Constructor.
1123 1118
    DijkstraWizard() : TR() {}
1124 1119

	
1125 1120
    /// Constructor that requires parameters.
1126 1121

	
1127 1122
    /// Constructor that requires parameters.
1128 1123
    /// These parameters will be the default values for the traits class.
1129 1124
    /// \param g The digraph the algorithm runs on.
1130 1125
    /// \param l The length map.
1131 1126
    DijkstraWizard(const Digraph &g, const LengthMap &l) :
1132 1127
      TR(g,l) {}
1133 1128

	
1134 1129
    ///Copy constructor
1135 1130
    DijkstraWizard(const TR &b) : TR(b) {}
1136 1131

	
1137 1132
    ~DijkstraWizard() {}
1138 1133

	
1139 1134
    ///Runs Dijkstra algorithm from the given source node.
1140 1135

	
1141 1136
    ///This method runs %Dijkstra algorithm from the given source node
1142 1137
    ///in order to compute the shortest path to each node.
1143 1138
    void run(Node s)
1144 1139
    {
1145 1140
      Dijkstra<Digraph,LengthMap,TR>
1146 1141
        dijk(*reinterpret_cast<const Digraph*>(Base::_g),
1147 1142
             *reinterpret_cast<const LengthMap*>(Base::_length));
1148 1143
      if (Base::_pred)
1149 1144
        dijk.predMap(*reinterpret_cast<PredMap*>(Base::_pred));
1150 1145
      if (Base::_dist)
1151 1146
        dijk.distMap(*reinterpret_cast<DistMap*>(Base::_dist));
1152 1147
      if (Base::_processed)
1153 1148
        dijk.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed));
1154 1149
      dijk.run(s);
1155 1150
    }
1156 1151

	
1157 1152
    ///Finds the shortest path between \c s and \c t.
1158 1153

	
1159 1154
    ///This method runs the %Dijkstra algorithm from node \c s
1160 1155
    ///in order to compute the shortest path to node \c t
1161 1156
    ///(it stops searching when \c t is processed).
1162 1157
    ///
1163 1158
    ///\return \c true if \c t is reachable form \c s.
1164 1159
    bool run(Node s, Node t)
1165 1160
    {
1166 1161
      Dijkstra<Digraph,LengthMap,TR>
1167 1162
        dijk(*reinterpret_cast<const Digraph*>(Base::_g),
1168 1163
             *reinterpret_cast<const LengthMap*>(Base::_length));
1169 1164
      if (Base::_pred)
1170 1165
        dijk.predMap(*reinterpret_cast<PredMap*>(Base::_pred));
1171 1166
      if (Base::_dist)
1172 1167
        dijk.distMap(*reinterpret_cast<DistMap*>(Base::_dist));
1173 1168
      if (Base::_processed)
1174 1169
        dijk.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed));
1175 1170
      dijk.run(s,t);
1176 1171
      if (Base::_path)
1177 1172
        *reinterpret_cast<Path*>(Base::_path) = dijk.path(t);
1178 1173
      if (Base::_di)
1179 1174
        *reinterpret_cast<Value*>(Base::_di) = dijk.dist(t);
1180 1175
      return dijk.reached(t);
1181 1176
    }
1182 1177

	
1183 1178
    template<class T>
1184 1179
    struct SetPredMapBase : public Base {
1185 1180
      typedef T PredMap;
1186 1181
      static PredMap *createPredMap(const Digraph &) { return 0; };
1187 1182
      SetPredMapBase(const TR &b) : TR(b) {}
1188 1183
    };
1189
    ///\brief \ref named-func-param "Named parameter"
1190
    ///for setting PredMap object.
1184

	
1185
    ///\brief \ref named-templ-param "Named parameter" for setting
1186
    ///the predecessor map.
1191 1187
    ///
1192
    ///\ref named-func-param "Named parameter"
1193
    ///for setting PredMap object.
1188
    ///\ref named-templ-param "Named parameter" function for setting
1189
    ///the map that stores the predecessor arcs of the nodes.
1194 1190
    template<class T>
1195 1191
    DijkstraWizard<SetPredMapBase<T> > predMap(const T &t)
1196 1192
    {
1197 1193
      Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t));
1198 1194
      return DijkstraWizard<SetPredMapBase<T> >(*this);
1199 1195
    }
1200 1196

	
1201 1197
    template<class T>
1202 1198
    struct SetDistMapBase : public Base {
1203 1199
      typedef T DistMap;
1204 1200
      static DistMap *createDistMap(const Digraph &) { return 0; };
1205 1201
      SetDistMapBase(const TR &b) : TR(b) {}
1206 1202
    };
1207
    ///\brief \ref named-func-param "Named parameter"
1208
    ///for setting DistMap object.
1203

	
1204
    ///\brief \ref named-templ-param "Named parameter" for setting
1205
    ///the distance map.
1209 1206
    ///
1210
    ///\ref named-func-param "Named parameter"
1211
    ///for setting DistMap object.
1207
    ///\ref named-templ-param "Named parameter" function for setting
1208
    ///the map that stores the distances of the nodes calculated
1209
    ///by the algorithm.
1212 1210
    template<class T>
1213 1211
    DijkstraWizard<SetDistMapBase<T> > distMap(const T &t)
1214 1212
    {
1215 1213
      Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t));
1216 1214
      return DijkstraWizard<SetDistMapBase<T> >(*this);
1217 1215
    }
1218 1216

	
1219 1217
    template<class T>
1220 1218
    struct SetProcessedMapBase : public Base {
1221 1219
      typedef T ProcessedMap;
1222 1220
      static ProcessedMap *createProcessedMap(const Digraph &) { return 0; };
1223 1221
      SetProcessedMapBase(const TR &b) : TR(b) {}
1224 1222
    };
1225
    ///\brief \ref named-func-param "Named parameter"
1226
    ///for setting ProcessedMap object.
1223

	
1224
    ///\brief \ref named-func-param "Named parameter" for setting
1225
    ///the processed map.
1227 1226
    ///
1228
    /// \ref named-func-param "Named parameter"
1229
    ///for setting ProcessedMap object.
1227
    ///\ref named-templ-param "Named parameter" function for setting
1228
    ///the map that indicates which nodes are processed.
1230 1229
    template<class T>
1231 1230
    DijkstraWizard<SetProcessedMapBase<T> > processedMap(const T &t)
1232 1231
    {
1233 1232
      Base::_processed=reinterpret_cast<void*>(const_cast<T*>(&t));
1234 1233
      return DijkstraWizard<SetProcessedMapBase<T> >(*this);
1235 1234
    }
1236 1235

	
1237 1236
    template<class T>
1238 1237
    struct SetPathBase : public Base {
1239 1238
      typedef T Path;
1240 1239
      SetPathBase(const TR &b) : TR(b) {}
1241 1240
    };
1241

	
1242 1242
    ///\brief \ref named-func-param "Named parameter"
1243 1243
    ///for getting the shortest path to the target node.
1244 1244
    ///
1245 1245
    ///\ref named-func-param "Named parameter"
1246 1246
    ///for getting the shortest path to the target node.
1247 1247
    template<class T>
1248 1248
    DijkstraWizard<SetPathBase<T> > path(const T &t)
1249 1249
    {
1250 1250
      Base::_path=reinterpret_cast<void*>(const_cast<T*>(&t));
1251 1251
      return DijkstraWizard<SetPathBase<T> >(*this);
1252 1252
    }
1253 1253

	
1254 1254
    ///\brief \ref named-func-param "Named parameter"
1255 1255
    ///for getting the distance of the target node.
1256 1256
    ///
1257 1257
    ///\ref named-func-param "Named parameter"
1258 1258
    ///for getting the distance of the target node.
1259 1259
    DijkstraWizard dist(const Value &d)
1260 1260
    {
1261 1261
      Base::_di=reinterpret_cast<void*>(const_cast<Value*>(&d));
1262 1262
      return *this;
1263 1263
    }
1264 1264

	
1265 1265
  };
1266 1266

	
1267 1267
  ///Function-type interface for Dijkstra algorithm.
1268 1268

	
1269 1269
  /// \ingroup shortest_path
1270 1270
  ///Function-type interface for Dijkstra algorithm.
1271 1271
  ///
1272 1272
  ///This function also has several \ref named-func-param "named parameters",
1273 1273
  ///they are declared as the members of class \ref DijkstraWizard.
1274 1274
  ///The following examples show how to use these parameters.
1275 1275
  ///\code
1276 1276
  ///  // Compute shortest path from node s to each node
1277 1277
  ///  dijkstra(g,length).predMap(preds).distMap(dists).run(s);
1278 1278
  ///
1279 1279
  ///  // Compute shortest path from s to t
1280 1280
  ///  bool reached = dijkstra(g,length).path(p).dist(d).run(s,t);
1281 1281
  ///\endcode
1282 1282
  ///\warning Don't forget to put the \ref DijkstraWizard::run(Node) "run()"
1283 1283
  ///to the end of the parameter list.
1284 1284
  ///\sa DijkstraWizard
1285 1285
  ///\sa Dijkstra
1286 1286
  template<typename GR, typename LEN>
1287 1287
  DijkstraWizard<DijkstraWizardBase<GR,LEN> >
1288 1288
  dijkstra(const GR &digraph, const LEN &length)
1289 1289
  {
1290 1290
    return DijkstraWizard<DijkstraWizardBase<GR,LEN> >(digraph,length);
1291 1291
  }
1292 1292

	
1293 1293
} //END OF NAMESPACE LEMON
1294 1294

	
1295 1295
#endif
Ignore white space 6 line context
1 1
/* -*- mode: C++; indent-tabs-mode: nil; -*-
2 2
 *
3 3
 * This file is a part of LEMON, a generic C++ optimization library.
4 4
 *
5 5
 * Copyright (C) 2003-2009
6 6
 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 7
 * (Egervary Research Group on Combinatorial Optimization, EGRES).
8 8
 *
9 9
 * Permission to use, modify and distribute this software is granted
10 10
 * provided that this copyright notice appears in all copies. For
11 11
 * precise terms see the accompanying LICENSE file.
12 12
 *
13 13
 * This software is provided "AS IS" with no warranty of any kind,
14 14
 * express or implied, and with no claim as to its suitability for any
15 15
 * purpose.
16 16
 *
17 17
 */
18 18

	
19 19
#ifndef LEMON_DIM2_H
20 20
#define LEMON_DIM2_H
21 21

	
22 22
#include <iostream>
23 23

	
24
///\ingroup misc
24
///\ingroup geomdat
25 25
///\file
26 26
///\brief A simple two dimensional vector and a bounding box implementation
27
///
28
/// The class \ref lemon::dim2::Point "dim2::Point" implements
29
/// a two dimensional vector with the usual operations.
30
///
31
/// The class \ref lemon::dim2::Box "dim2::Box" can be used to determine
32
/// the rectangular bounding box of a set of
33
/// \ref lemon::dim2::Point "dim2::Point"'s.
34 27

	
35 28
namespace lemon {
36 29

	
37 30
  ///Tools for handling two dimensional coordinates
38 31

	
39 32
  ///This namespace is a storage of several
40 33
  ///tools for handling two dimensional coordinates
41 34
  namespace dim2 {
42 35

	
43
  /// \addtogroup misc
36
  /// \addtogroup geomdat
44 37
  /// @{
45 38

	
46 39
  /// Two dimensional vector (plain vector)
47 40

	
48 41
  /// A simple two dimensional vector (plain vector) implementation
49 42
  /// with the usual vector operations.
50 43
  template<typename T>
51 44
    class Point {
52 45

	
53 46
    public:
54 47

	
55 48
      typedef T Value;
56 49

	
57 50
      ///First coordinate
58 51
      T x;
59 52
      ///Second coordinate
60 53
      T y;
61 54

	
62 55
      ///Default constructor
63 56
      Point() {}
64 57

	
65 58
      ///Construct an instance from coordinates
66 59
      Point(T a, T b) : x(a), y(b) { }
67 60

	
68 61
      ///Returns the dimension of the vector (i.e. returns 2).
69 62

	
70 63
      ///The dimension of the vector.
71 64
      ///This function always returns 2.
72 65
      int size() const { return 2; }
73 66

	
74 67
      ///Subscripting operator
75 68

	
76 69
      ///\c p[0] is \c p.x and \c p[1] is \c p.y
77 70
      ///
78 71
      T& operator[](int idx) { return idx == 0 ? x : y; }
79 72

	
80 73
      ///Const subscripting operator
81 74

	
82 75
      ///\c p[0] is \c p.x and \c p[1] is \c p.y
83 76
      ///
84 77
      const T& operator[](int idx) const { return idx == 0 ? x : y; }
85 78

	
86 79
      ///Conversion constructor
87 80
      template<class TT> Point(const Point<TT> &p) : x(p.x), y(p.y) {}
88 81

	
89 82
      ///Give back the square of the norm of the vector
90 83
      T normSquare() const {
91 84
        return x*x+y*y;
92 85
      }
93 86

	
94 87
      ///Increment the left hand side by \c u
95 88
      Point<T>& operator +=(const Point<T>& u) {
96 89
        x += u.x;
97 90
        y += u.y;
98 91
        return *this;
99 92
      }
100 93

	
101 94
      ///Decrement the left hand side by \c u
102 95
      Point<T>& operator -=(const Point<T>& u) {
103 96
        x -= u.x;
104 97
        y -= u.y;
105 98
        return *this;
106 99
      }
107 100

	
108 101
      ///Multiply the left hand side with a scalar
109 102
      Point<T>& operator *=(const T &u) {
110 103
        x *= u;
111 104
        y *= u;
112 105
        return *this;
113 106
      }
114 107

	
115 108
      ///Divide the left hand side by a scalar
116 109
      Point<T>& operator /=(const T &u) {
117 110
        x /= u;
118 111
        y /= u;
119 112
        return *this;
120 113
      }
121 114

	
122 115
      ///Return the scalar product of two vectors
123 116
      T operator *(const Point<T>& u) const {
124 117
        return x*u.x+y*u.y;
125 118
      }
126 119

	
127 120
      ///Return the sum of two vectors
128 121
      Point<T> operator+(const Point<T> &u) const {
129 122
        Point<T> b=*this;
130 123
        return b+=u;
131 124
      }
132 125

	
133 126
      ///Return the negative of the vector
134 127
      Point<T> operator-() const {
135 128
        Point<T> b=*this;
136 129
        b.x=-b.x; b.y=-b.y;
137 130
        return b;
138 131
      }
139 132

	
140 133
      ///Return the difference of two vectors
141 134
      Point<T> operator-(const Point<T> &u) const {
142 135
        Point<T> b=*this;
143 136
        return b-=u;
144 137
      }
145 138

	
146 139
      ///Return a vector multiplied by a scalar
147 140
      Point<T> operator*(const T &u) const {
148 141
        Point<T> b=*this;
149 142
        return b*=u;
150 143
      }
151 144

	
152 145
      ///Return a vector divided by a scalar
153 146
      Point<T> operator/(const T &u) const {
154 147
        Point<T> b=*this;
155 148
        return b/=u;
156 149
      }
157 150

	
158 151
      ///Test equality
159 152
      bool operator==(const Point<T> &u) const {
160 153
        return (x==u.x) && (y==u.y);
161 154
      }
162 155

	
163 156
      ///Test inequality
164 157
      bool operator!=(Point u) const {
165 158
        return  (x!=u.x) || (y!=u.y);
166 159
      }
167 160

	
168 161
    };
169 162

	
170 163
  ///Return a Point
171 164

	
172 165
  ///Return a Point.
173 166
  ///\relates Point
174 167
  template <typename T>
175 168
  inline Point<T> makePoint(const T& x, const T& y) {
176 169
    return Point<T>(x, y);
177 170
  }
178 171

	
179 172
  ///Return a vector multiplied by a scalar
180 173

	
181 174
  ///Return a vector multiplied by a scalar.
182 175
  ///\relates Point
183 176
  template<typename T> Point<T> operator*(const T &u,const Point<T> &x) {
184 177
    return x*u;
185 178
  }
186 179

	
187 180
  ///Read a plain vector from a stream
188 181

	
189 182
  ///Read a plain vector from a stream.
190 183
  ///\relates Point
191 184
  ///
192 185
  template<typename T>
193 186
  inline std::istream& operator>>(std::istream &is, Point<T> &z) {
194 187
    char c;
195 188
    if (is >> c) {
196 189
      if (c != '(') is.putback(c);
197 190
    } else {
198 191
      is.clear();
199 192
    }
200 193
    if (!(is >> z.x)) return is;
201 194
    if (is >> c) {
202 195
      if (c != ',') is.putback(c);
203 196
    } else {
204 197
      is.clear();
205 198
    }
206 199
    if (!(is >> z.y)) return is;
207 200
    if (is >> c) {
208 201
      if (c != ')') is.putback(c);
209 202
    } else {
210 203
      is.clear();
211 204
    }
212 205
    return is;
213 206
  }
214 207

	
215 208
  ///Write a plain vector to a stream
216 209

	
217 210
  ///Write a plain vector to a stream.
218 211
  ///\relates Point
219 212
  ///
220 213
  template<typename T>
221 214
  inline std::ostream& operator<<(std::ostream &os, const Point<T>& z)
222 215
  {
223 216
    os << "(" << z.x << "," << z.y << ")";
224 217
    return os;
225 218
  }
226 219

	
227 220
  ///Rotate by 90 degrees
228 221

	
229 222
  ///Returns the parameter rotated by 90 degrees in positive direction.
230 223
  ///\relates Point
231 224
  ///
232 225
  template<typename T>
233 226
  inline Point<T> rot90(const Point<T> &z)
234 227
  {
235 228
    return Point<T>(-z.y,z.x);
236 229
  }
237 230

	
238 231
  ///Rotate by 180 degrees
239 232

	
240 233
  ///Returns the parameter rotated by 180 degrees.
241 234
  ///\relates Point
242 235
  ///
243 236
  template<typename T>
244 237
  inline Point<T> rot180(const Point<T> &z)
245 238
  {
246 239
    return Point<T>(-z.x,-z.y);
247 240
  }
248 241

	
249 242
  ///Rotate by 270 degrees
250 243

	
251 244
  ///Returns the parameter rotated by 90 degrees in negative direction.
252 245
  ///\relates Point
253 246
  ///
254 247
  template<typename T>
255 248
  inline Point<T> rot270(const Point<T> &z)
256 249
  {
257 250
    return Point<T>(z.y,-z.x);
258 251
  }
259 252

	
260 253

	
261 254

	
262 255
  /// Bounding box of plain vectors (points).
263 256

	
264 257
  /// A class to calculate or store the bounding box of plain vectors
265 258
  /// (\ref Point "points").
266 259
  template<typename T>
267 260
  class Box {
268 261
      Point<T> _bottom_left, _top_right;
269 262
      bool _empty;
270 263
    public:
271 264

	
272 265
      ///Default constructor: creates an empty box
273 266
      Box() { _empty = true; }
274 267

	
275 268
      ///Construct a box from one point
276 269
      Box(Point<T> a) {
277 270
        _bottom_left = _top_right = a;
278 271
        _empty = false;
279 272
      }
280 273

	
281 274
      ///Construct a box from two points
282 275

	
283 276
      ///Construct a box from two points.
284 277
      ///\param a The bottom left corner.
285 278
      ///\param b The top right corner.
286 279
      ///\warning The coordinates of the bottom left corner must be no more
287 280
      ///than those of the top right one.
288 281
      Box(Point<T> a,Point<T> b)
289 282
      {
290 283
        _bottom_left = a;
291 284
        _top_right = b;
292 285
        _empty = false;
293 286
      }
294 287

	
295 288
      ///Construct a box from four numbers
296 289

	
297 290
      ///Construct a box from four numbers.
298 291
      ///\param l The left side of the box.
299 292
      ///\param b The bottom of the box.
300 293
      ///\param r The right side of the box.
301 294
      ///\param t The top of the box.
302 295
      ///\warning The left side must be no more than the right side and
303 296
      ///bottom must be no more than the top.
304 297
      Box(T l,T b,T r,T t)
305 298
      {
306 299
        _bottom_left=Point<T>(l,b);
307 300
        _top_right=Point<T>(r,t);
308 301
        _empty = false;
309 302
      }
310 303

	
311 304
      ///Return \c true if the box is empty.
312 305

	
313 306
      ///Return \c true if the box is empty (i.e. return \c false
314 307
      ///if at least one point was added to the box or the coordinates of
315 308
      ///the box were set).
316 309
      ///
317 310
      ///The coordinates of an empty box are not defined.
318 311
      bool empty() const {
319 312
        return _empty;
320 313
      }
321 314

	
322 315
      ///Make the box empty
323 316
      void clear() {
324 317
        _empty = true;
325 318
      }
326 319

	
327 320
      ///Give back the bottom left corner of the box
328 321

	
329 322
      ///Give back the bottom left corner of the box.
330 323
      ///If the box is empty, then the return value is not defined.
331 324
      Point<T> bottomLeft() const {
332 325
        return _bottom_left;
333 326
      }
334 327

	
335 328
      ///Set the bottom left corner of the box
336 329

	
337 330
      ///Set the bottom left corner of the box.
338 331
      ///\pre The box must not be empty.
339 332
      void bottomLeft(Point<T> p) {
340 333
        _bottom_left = p;
341 334
      }
342 335

	
343 336
      ///Give back the top right corner of the box
344 337

	
345 338
      ///Give back the top right corner of the box.
346 339
      ///If the box is empty, then the return value is not defined.
347 340
      Point<T> topRight() const {
348 341
        return _top_right;
349 342
      }
350 343

	
351 344
      ///Set the top right corner of the box
352 345

	
353 346
      ///Set the top right corner of the box.
354 347
      ///\pre The box must not be empty.
355 348
      void topRight(Point<T> p) {
356 349
        _top_right = p;
357 350
      }
358 351

	
359 352
      ///Give back the bottom right corner of the box
360 353

	
361 354
      ///Give back the bottom right corner of the box.
362 355
      ///If the box is empty, then the return value is not defined.
363 356
      Point<T> bottomRight() const {
364 357
        return Point<T>(_top_right.x,_bottom_left.y);
365 358
      }
366 359

	
367 360
      ///Set the bottom right corner of the box
368 361

	
369 362
      ///Set the bottom right corner of the box.
370 363
      ///\pre The box must not be empty.
371 364
      void bottomRight(Point<T> p) {
372 365
        _top_right.x = p.x;
373 366
        _bottom_left.y = p.y;
374 367
      }
375 368

	
376 369
      ///Give back the top left corner of the box
377 370

	
378 371
      ///Give back the top left corner of the box.
379 372
      ///If the box is empty, then the return value is not defined.
380 373
      Point<T> topLeft() const {
381 374
        return Point<T>(_bottom_left.x,_top_right.y);
382 375
      }
383 376

	
384 377
      ///Set the top left corner of the box
385 378

	
386 379
      ///Set the top left corner of the box.
387 380
      ///\pre The box must not be empty.
388 381
      void topLeft(Point<T> p) {
389 382
        _top_right.y = p.y;
390 383
        _bottom_left.x = p.x;
391 384
      }
392 385

	
393 386
      ///Give back the bottom of the box
394 387

	
395 388
      ///Give back the bottom of the box.
396 389
      ///If the box is empty, then the return value is not defined.
397 390
      T bottom() const {
398 391
        return _bottom_left.y;
399 392
      }
400 393

	
401 394
      ///Set the bottom of the box
402 395

	
403 396
      ///Set the bottom of the box.
404 397
      ///\pre The box must not be empty.
405 398
      void bottom(T t) {
406 399
        _bottom_left.y = t;
407 400
      }
408 401

	
409 402
      ///Give back the top of the box
410 403

	
411 404
      ///Give back the top of the box.
412 405
      ///If the box is empty, then the return value is not defined.
413 406
      T top() const {
414 407
        return _top_right.y;
415 408
      }
416 409

	
417 410
      ///Set the top of the box
418 411

	
419 412
      ///Set the top of the box.
420 413
      ///\pre The box must not be empty.
421 414
      void top(T t) {
422 415
        _top_right.y = t;
423 416
      }
424 417

	
425 418
      ///Give back the left side of the box
426 419

	
427 420
      ///Give back the left side of the box.

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