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/* -*- C++ -*- |
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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) 2003-2008 |
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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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#ifndef LEMON_BFS_H |
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#define LEMON_BFS_H |
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///\ingroup search |
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///\file |
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///\brief Bfs algorithm. |
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#include <lemon/list_graph.h> |
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#include <lemon/graph_utils.h> |
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#include <lemon/bits/path_dump.h> |
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#include <lemon/bits/invalid.h> |
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#include <lemon/error.h> |
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#include <lemon/maps.h> |
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namespace lemon { |
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///Default traits class of Bfs class. |
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///Default traits class of Bfs class. |
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///\param GR Digraph type. |
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template<class GR> |
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struct BfsDefaultTraits |
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{ |
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///The digraph type the algorithm runs on. |
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typedef GR Digraph; |
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///\brief The type of the map that stores the last |
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///arcs of the shortest paths. |
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/// |
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///The type of the map that stores the last |
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///arcs of the shortest paths. |
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///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
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/// |
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typedef typename Digraph::template NodeMap<typename GR::Arc> PredMap; |
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///Instantiates a PredMap. |
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|
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///This function instantiates a \ref PredMap. |
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///\param G is the digraph, to which we would like to define the PredMap. |
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///\todo The digraph alone may be insufficient to initialize |
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static PredMap *createPredMap(const GR &G) |
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{ |
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return new PredMap(G); |
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} |
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///The type of the map that indicates which nodes are processed. |
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|
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///The type of the map that indicates which nodes are processed. |
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///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
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///\todo named parameter to set this type, function to read and write. |
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typedef NullMap<typename Digraph::Node,bool> ProcessedMap; |
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///Instantiates a ProcessedMap. |
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|
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///This function instantiates a \ref ProcessedMap. |
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///\param g is the digraph, to which |
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///we would like to define the \ref ProcessedMap |
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#ifdef DOXYGEN |
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static ProcessedMap *createProcessedMap(const GR &g) |
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#else |
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static ProcessedMap *createProcessedMap(const GR &) |
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#endif |
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{ |
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return new ProcessedMap(); |
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} |
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///The type of the map that indicates which nodes are reached. |
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|
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///The type of the map that indicates which nodes are reached. |
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///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
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///\todo named parameter to set this type, function to read and write. |
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typedef typename Digraph::template NodeMap<bool> ReachedMap; |
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///Instantiates a ReachedMap. |
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///This function instantiates a \ref ReachedMap. |
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///\param G is the digraph, to which |
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///we would like to define the \ref ReachedMap. |
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static ReachedMap *createReachedMap(const GR &G) |
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{ |
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return new ReachedMap(G); |
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} |
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///The type of the map that stores the dists of the nodes. |
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///The type of the map that stores the dists of the nodes. |
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///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
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/// |
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typedef typename Digraph::template NodeMap<int> DistMap; |
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///Instantiates a DistMap. |
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///This function instantiates a \ref DistMap. |
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///\param G is the digraph, to which we would like to define the \ref DistMap |
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static DistMap *createDistMap(const GR &G) |
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{ |
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return new DistMap(G); |
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} |
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}; |
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///%BFS algorithm class. |
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///\ingroup search |
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///This class provides an efficient implementation of the %BFS algorithm. |
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/// |
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///\param GR The digraph type the algorithm runs on. The default value is |
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///\ref ListDigraph. The value of GR is not used directly by Bfs, it |
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///is only passed to \ref BfsDefaultTraits. |
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///\param TR Traits class to set various data types used by the algorithm. |
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///The default traits class is |
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///\ref BfsDefaultTraits "BfsDefaultTraits<GR>". |
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///See \ref BfsDefaultTraits for the documentation of |
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///a Bfs traits class. |
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/// |
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///\author Alpar Juttner |
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#ifdef DOXYGEN |
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template <typename GR, |
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typename TR> |
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#else |
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template <typename GR=ListDigraph, |
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typename TR=BfsDefaultTraits<GR> > |
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#endif |
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class Bfs { |
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public: |
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/** |
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* \brief \ref Exception for uninitialized parameters. |
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* |
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* This error represents problems in the initialization |
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* of the parameters of the algorithms. |
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*/ |
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class UninitializedParameter : public lemon::UninitializedParameter { |
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public: |
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virtual const char* what() const throw() { |
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return "lemon::Bfs::UninitializedParameter"; |
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} |
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}; |
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typedef TR Traits; |
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///The type of the underlying digraph. |
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typedef typename TR::Digraph Digraph; |
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///\brief The type of the map that stores the last |
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///arcs of the shortest paths. |
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typedef typename TR::PredMap PredMap; |
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///The type of the map indicating which nodes are reached. |
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typedef typename TR::ReachedMap ReachedMap; |
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///The type of the map indicating which nodes are processed. |
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typedef typename TR::ProcessedMap ProcessedMap; |
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///The type of the map that stores the dists of the nodes. |
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typedef typename TR::DistMap DistMap; |
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private: |
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typedef typename Digraph::Node Node; |
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typedef typename Digraph::NodeIt NodeIt; |
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typedef typename Digraph::Arc Arc; |
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typedef typename Digraph::OutArcIt OutArcIt; |
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/// Pointer to the underlying digraph. |
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const Digraph *G; |
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///Pointer to the map of predecessors arcs. |
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PredMap *_pred; |
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///Indicates if \ref _pred is locally allocated (\c true) or not. |
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bool local_pred; |
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///Pointer to the map of distances. |
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DistMap *_dist; |
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///Indicates if \ref _dist is locally allocated (\c true) or not. |
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bool local_dist; |
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///Pointer to the map of reached status of the nodes. |
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ReachedMap *_reached; |
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///Indicates if \ref _reached is locally allocated (\c true) or not. |
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bool local_reached; |
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///Pointer to the map of processed status of the nodes. |
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ProcessedMap *_processed; |
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///Indicates if \ref _processed is locally allocated (\c true) or not. |
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bool local_processed; |
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std::vector<typename Digraph::Node> _queue; |
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int _queue_head,_queue_tail,_queue_next_dist; |
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int _curr_dist; |
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///Creates the maps if necessary. |
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///\todo Better memory allocation (instead of new). |
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void create_maps() |
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{ |
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if(!_pred) { |
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local_pred = true; |
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_pred = Traits::createPredMap(*G); |
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} |
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if(!_dist) { |
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local_dist = true; |
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_dist = Traits::createDistMap(*G); |
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} |
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if(!_reached) { |
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local_reached = true; |
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_reached = Traits::createReachedMap(*G); |
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} |
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if(!_processed) { |
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local_processed = true; |
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_processed = Traits::createProcessedMap(*G); |
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} |
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} |
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protected: |
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Bfs() {} |
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public: |
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typedef Bfs Create; |
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///\name Named template parameters |
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///@{ |
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template <class T> |
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struct DefPredMapTraits : public Traits { |
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typedef T PredMap; |
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static PredMap *createPredMap(const Digraph &) |
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{ |
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throw UninitializedParameter(); |
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} |
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}; |
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///\brief \ref named-templ-param "Named parameter" for setting |
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///PredMap type |
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/// |
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///\ref named-templ-param "Named parameter" for setting PredMap type |
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/// |
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template <class T> |
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struct DefPredMap : public Bfs< Digraph, DefPredMapTraits<T> > { |
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typedef Bfs< Digraph, DefPredMapTraits<T> > Create; |
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}; |
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template <class T> |
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struct DefDistMapTraits : public Traits { |
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typedef T DistMap; |
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static DistMap *createDistMap(const Digraph &) |
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{ |
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throw UninitializedParameter(); |
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} |
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}; |
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///\brief \ref named-templ-param "Named parameter" for setting |
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///DistMap type |
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/// |
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///\ref named-templ-param "Named parameter" for setting DistMap type |
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/// |
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template <class T> |
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struct DefDistMap : public Bfs< Digraph, DefDistMapTraits<T> > { |
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typedef Bfs< Digraph, DefDistMapTraits<T> > Create; |
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}; |
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template <class T> |
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struct DefReachedMapTraits : public Traits { |
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typedef T ReachedMap; |
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static ReachedMap *createReachedMap(const Digraph &) |
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{ |
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throw UninitializedParameter(); |
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} |
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}; |
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///\brief \ref named-templ-param "Named parameter" for setting |
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///ReachedMap type |
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/// |
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///\ref named-templ-param "Named parameter" for setting ReachedMap type |
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/// |
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template <class T> |
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struct DefReachedMap : public Bfs< Digraph, DefReachedMapTraits<T> > { |
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typedef Bfs< Digraph, DefReachedMapTraits<T> > Create; |
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}; |
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template <class T> |
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struct DefProcessedMapTraits : public Traits { |
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typedef T ProcessedMap; |
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static ProcessedMap *createProcessedMap(const Digraph &) |
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{ |
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throw UninitializedParameter(); |
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} |
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}; |
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///\brief \ref named-templ-param "Named parameter" for setting |
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///ProcessedMap type |
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/// |
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///\ref named-templ-param "Named parameter" for setting ProcessedMap type |
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/// |
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template <class T> |
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struct DefProcessedMap : public Bfs< Digraph, DefProcessedMapTraits<T> > { |
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typedef Bfs< Digraph, DefProcessedMapTraits<T> > Create; |
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}; |
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struct DefDigraphProcessedMapTraits : public Traits { |
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typedef typename Digraph::template NodeMap<bool> ProcessedMap; |
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static ProcessedMap *createProcessedMap(const Digraph &G) |
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{ |
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return new ProcessedMap(G); |
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} |
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}; |
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///\brief \ref named-templ-param "Named parameter" |
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///for setting the ProcessedMap type to be Digraph::NodeMap<bool>. |
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/// |
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///\ref named-templ-param "Named parameter" |
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///for setting the ProcessedMap type to be Digraph::NodeMap<bool>. |
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///If you don't set it explicitly, it will be automatically allocated. |
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template <class T> |
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struct DefProcessedMapToBeDefaultMap : |
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public Bfs< Digraph, DefDigraphProcessedMapTraits> { |
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typedef Bfs< Digraph, DefDigraphProcessedMapTraits> Create; |
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}; |
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///@} |
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public: |
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///Constructor. |
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///\param _G the digraph the algorithm will run on. |
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/// |
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Bfs(const Digraph& _G) : |
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G(&_G), |
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_pred(NULL), local_pred(false), |
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_dist(NULL), local_dist(false), |
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_reached(NULL), local_reached(false), |
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_processed(NULL), local_processed(false) |
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{ } |
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///Destructor. |
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~Bfs() |
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{ |
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if(local_pred) delete _pred; |
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if(local_dist) delete _dist; |
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if(local_reached) delete _reached; |
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if(local_processed) delete _processed; |
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} |
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///Sets the map storing the predecessor arcs. |
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|
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///Sets the map storing the predecessor arcs. |
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///If you don't use this function before calling \ref run(), |
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///it will allocate one. The destructor deallocates this |
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///automatically allocated map, of course. |
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///\return <tt> (*this) </tt> |
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Bfs &predMap(PredMap &m) |
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{ |
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if(local_pred) { |
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delete _pred; |
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local_pred=false; |
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} |
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_pred = &m; |
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return *this; |
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} |
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|
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///Sets the map indicating the reached nodes. |
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|
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///Sets the map indicating the reached nodes. |
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///If you don't use this function before calling \ref run(), |
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///it will allocate one. The destructor deallocates this |
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///automatically allocated map, of course. |
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///\return <tt> (*this) </tt> |
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Bfs &reachedMap(ReachedMap &m) |
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{ |
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if(local_reached) { |
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delete _reached; |
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local_reached=false; |
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} |
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_reached = &m; |
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return *this; |
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} |
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|
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///Sets the map indicating the processed nodes. |
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380 |
|
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///Sets the map indicating the processed nodes. |
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///If you don't use this function before calling \ref run(), |
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///it will allocate one. The destructor deallocates this |
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///automatically allocated map, of course. |
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///\return <tt> (*this) </tt> |
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Bfs &processedMap(ProcessedMap &m) |
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{ |
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if(local_processed) { |
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delete _processed; |
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local_processed=false; |
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} |
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_processed = &m; |
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return *this; |
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} |
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|
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///Sets the map storing the distances calculated by the algorithm. |
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397 |
|
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///Sets the map storing the distances calculated by the algorithm. |
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///If you don't use this function before calling \ref run(), |
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///it will allocate one. The destructor deallocates this |
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///automatically allocated map, of course. |
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///\return <tt> (*this) </tt> |
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Bfs &distMap(DistMap &m) |
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{ |
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if(local_dist) { |
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delete _dist; |
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local_dist=false; |
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} |
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_dist = &m; |
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return *this; |
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} |
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412 |
|
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public: |
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///\name Execution control |
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///The simplest way to execute the algorithm is to use |
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///one of the member functions called \c run(...). |
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///\n |
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///If you need more control on the execution, |
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///first you must call \ref init(), then you can add several source nodes |
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///with \ref addSource(). |
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///Finally \ref start() will perform the actual path |
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///computation. |
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423 |
|
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///@{ |
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425 |
|
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426 |
///\brief Initializes the internal data structures. |
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/// |
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428 |
///Initializes the internal data structures. |
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429 |
/// |
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430 |
void init() |
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431 |
{ |
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432 |
create_maps(); |
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433 |
_queue.resize(countNodes(*G)); |
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_queue_head=_queue_tail=0; |
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_curr_dist=1; |
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436 |
for ( NodeIt u(*G) ; u!=INVALID ; ++u ) { |
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_pred->set(u,INVALID); |
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_reached->set(u,false); |
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_processed->set(u,false); |
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} |
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} |
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442 |
|
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///Adds a new source node. |
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444 |
|
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///Adds a new source node to the set of nodes to be processed. |
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/// |
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447 |
void addSource(Node s) |
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{ |
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if(!(*_reached)[s]) |
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{ |
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_reached->set(s,true); |
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_pred->set(s,INVALID); |
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_dist->set(s,0); |
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_queue[_queue_head++]=s; |
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_queue_next_dist=_queue_head; |
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} |
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} |
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458 |
|
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///Processes the next node. |
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460 |
|
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///Processes the next node. |
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462 |
/// |
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463 |
///\return The processed node. |
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464 |
/// |
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465 |
///\warning The queue must not be empty! |
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466 |
Node processNextNode() |
|
467 |
{ |
|
468 |
if(_queue_tail==_queue_next_dist) { |
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469 |
_curr_dist++; |
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470 |
_queue_next_dist=_queue_head; |
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471 |
} |
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472 |
Node n=_queue[_queue_tail++]; |
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473 |
_processed->set(n,true); |
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474 |
Node m; |
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475 |
for(OutArcIt e(*G,n);e!=INVALID;++e) |
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476 |
if(!(*_reached)[m=G->target(e)]) { |
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477 |
_queue[_queue_head++]=m; |
|
478 |
_reached->set(m,true); |
|
479 |
_pred->set(m,e); |
|
480 |
_dist->set(m,_curr_dist); |
|
481 |
} |
|
482 |
return n; |
|
483 |
} |
|
484 |
|
|
485 |
///Processes the next node. |
|
486 |
|
|
487 |
///Processes the next node. And checks that the given target node |
|
488 |
///is reached. If the target node is reachable from the processed |
|
489 |
///node then the reached parameter will be set true. The reached |
|
490 |
///parameter should be initially false. |
|
491 |
/// |
|
492 |
///\param target The target node. |
|
493 |
///\retval reach Indicates that the target node is reached. |
|
494 |
///\return The processed node. |
|
495 |
/// |
|
496 |
///\warning The queue must not be empty! |
|
497 |
Node processNextNode(Node target, bool& reach) |
|
498 |
{ |
|
499 |
if(_queue_tail==_queue_next_dist) { |
|
500 |
_curr_dist++; |
|
501 |
_queue_next_dist=_queue_head; |
|
502 |
} |
|
503 |
Node n=_queue[_queue_tail++]; |
|
504 |
_processed->set(n,true); |
|
505 |
Node m; |
|
506 |
for(OutArcIt e(*G,n);e!=INVALID;++e) |
|
507 |
if(!(*_reached)[m=G->target(e)]) { |
|
508 |
_queue[_queue_head++]=m; |
|
509 |
_reached->set(m,true); |
|
510 |
_pred->set(m,e); |
|
511 |
_dist->set(m,_curr_dist); |
|
512 |
reach = reach || (target == m); |
|
513 |
} |
|
514 |
return n; |
|
515 |
} |
|
516 |
|
|
517 |
///Processes the next node. |
|
518 |
|
|
519 |
///Processes the next node. And checks that at least one of |
|
520 |
///reached node has true value in the \c nm node map. If one node |
|
521 |
///with true value is reachable from the processed node then the |
|
522 |
///rnode parameter will be set to the first of such nodes. |
|
523 |
/// |
|
524 |
///\param nm The node map of possible targets. |
|
525 |
///\retval rnode The reached target node. |
|
526 |
///\return The processed node. |
|
527 |
/// |
|
528 |
///\warning The queue must not be empty! |
|
529 |
template<class NM> |
|
530 |
Node processNextNode(const NM& nm, Node& rnode) |
|
531 |
{ |
|
532 |
if(_queue_tail==_queue_next_dist) { |
|
533 |
_curr_dist++; |
|
534 |
_queue_next_dist=_queue_head; |
|
535 |
} |
|
536 |
Node n=_queue[_queue_tail++]; |
|
537 |
_processed->set(n,true); |
|
538 |
Node m; |
|
539 |
for(OutArcIt e(*G,n);e!=INVALID;++e) |
|
540 |
if(!(*_reached)[m=G->target(e)]) { |
|
541 |
_queue[_queue_head++]=m; |
|
542 |
_reached->set(m,true); |
|
543 |
_pred->set(m,e); |
|
544 |
_dist->set(m,_curr_dist); |
|
545 |
if (nm[m] && rnode == INVALID) rnode = m; |
|
546 |
} |
|
547 |
return n; |
|
548 |
} |
|
549 |
|
|
550 |
///Next node to be processed. |
|
551 |
|
|
552 |
///Next node to be processed. |
|
553 |
/// |
|
554 |
///\return The next node to be processed or INVALID if the queue is |
|
555 |
/// empty. |
|
556 |
Node nextNode() |
|
557 |
{ |
|
558 |
return _queue_tail<_queue_head?_queue[_queue_tail]:INVALID; |
|
559 |
} |
|
560 |
|
|
561 |
///\brief Returns \c false if there are nodes |
|
562 |
///to be processed in the queue |
|
563 |
/// |
|
564 |
///Returns \c false if there are nodes |
|
565 |
///to be processed in the queue |
|
566 |
bool emptyQueue() { return _queue_tail==_queue_head; } |
|
567 |
///Returns the number of the nodes to be processed. |
|
568 |
|
|
569 |
///Returns the number of the nodes to be processed in the queue. |
|
570 |
int queueSize() { return _queue_head-_queue_tail; } |
|
571 |
|
|
572 |
///Executes the algorithm. |
|
573 |
|
|
574 |
///Executes the algorithm. |
|
575 |
/// |
|
576 |
///\pre init() must be called and at least one node should be added |
|
577 |
///with addSource() before using this function. |
|
578 |
/// |
|
579 |
///This method runs the %BFS algorithm from the root node(s) |
|
580 |
///in order to |
|
581 |
///compute the |
|
582 |
///shortest path to each node. The algorithm computes |
|
583 |
///- The shortest path tree. |
|
584 |
///- The distance of each node from the root(s). |
|
585 |
void start() |
|
586 |
{ |
|
587 |
while ( !emptyQueue() ) processNextNode(); |
|
588 |
} |
|
589 |
|
|
590 |
///Executes the algorithm until \c dest is reached. |
|
591 |
|
|
592 |
///Executes the algorithm until \c dest is reached. |
|
593 |
/// |
|
594 |
///\pre init() must be called and at least one node should be added |
|
595 |
///with addSource() before using this function. |
|
596 |
/// |
|
597 |
///This method runs the %BFS algorithm from the root node(s) |
|
598 |
///in order to compute the shortest path to \c dest. |
|
599 |
///The algorithm computes |
|
600 |
///- The shortest path to \c dest. |
|
601 |
///- The distance of \c dest from the root(s). |
|
602 |
void start(Node dest) |
|
603 |
{ |
|
604 |
bool reach = false; |
|
605 |
while ( !emptyQueue() && !reach ) processNextNode(dest, reach); |
|
606 |
} |
|
607 |
|
|
608 |
///Executes the algorithm until a condition is met. |
|
609 |
|
|
610 |
///Executes the algorithm until a condition is met. |
|
611 |
/// |
|
612 |
///\pre init() must be called and at least one node should be added |
|
613 |
///with addSource() before using this function. |
|
614 |
/// |
|
615 |
///\param nm must be a bool (or convertible) node map. The |
|
616 |
///algorithm will stop when it reaches a node \c v with |
|
617 |
/// <tt>nm[v]</tt> true. |
|
618 |
/// |
|
619 |
///\return The reached node \c v with <tt>nm[v]</tt> true or |
|
620 |
///\c INVALID if no such node was found. |
|
621 |
template<class NM> |
|
622 |
Node start(const NM &nm) |
|
623 |
{ |
|
624 |
Node rnode = INVALID; |
|
625 |
while ( !emptyQueue() && rnode == INVALID ) { |
|
626 |
processNextNode(nm, rnode); |
|
627 |
} |
|
628 |
return rnode; |
|
629 |
} |
|
630 |
|
|
631 |
///Runs %BFS algorithm from node \c s. |
|
632 |
|
|
633 |
///This method runs the %BFS algorithm from a root node \c s |
|
634 |
///in order to |
|
635 |
///compute the |
|
636 |
///shortest path to each node. The algorithm computes |
|
637 |
///- The shortest path tree. |
|
638 |
///- The distance of each node from the root. |
|
639 |
/// |
|
640 |
///\note b.run(s) is just a shortcut of the following code. |
|
641 |
///\code |
|
642 |
/// b.init(); |
|
643 |
/// b.addSource(s); |
|
644 |
/// b.start(); |
|
645 |
///\endcode |
|
646 |
void run(Node s) { |
|
647 |
init(); |
|
648 |
addSource(s); |
|
649 |
start(); |
|
650 |
} |
|
651 |
|
|
652 |
///Finds the shortest path between \c s and \c t. |
|
653 |
|
|
654 |
///Finds the shortest path between \c s and \c t. |
|
655 |
/// |
|
656 |
///\return The length of the shortest s---t path if there exists one, |
|
657 |
///0 otherwise. |
|
658 |
///\note Apart from the return value, b.run(s) is |
|
659 |
///just a shortcut of the following code. |
|
660 |
///\code |
|
661 |
/// b.init(); |
|
662 |
/// b.addSource(s); |
|
663 |
/// b.start(t); |
|
664 |
///\endcode |
|
665 |
int run(Node s,Node t) { |
|
666 |
init(); |
|
667 |
addSource(s); |
|
668 |
start(t); |
|
669 |
return reached(t) ? _curr_dist : 0; |
|
670 |
} |
|
671 |
|
|
672 |
///@} |
|
673 |
|
|
674 |
///\name Query Functions |
|
675 |
///The result of the %BFS algorithm can be obtained using these |
|
676 |
///functions.\n |
|
677 |
///Before the use of these functions, |
|
678 |
///either run() or start() must be calleb. |
|
679 |
|
|
680 |
///@{ |
|
681 |
|
|
682 |
typedef PredMapPath<Digraph, PredMap> Path; |
|
683 |
|
|
684 |
///Gives back the shortest path. |
|
685 |
|
|
686 |
///Gives back the shortest path. |
|
687 |
///\pre The \c t should be reachable from the source. |
|
688 |
Path path(Node t) |
|
689 |
{ |
|
690 |
return Path(*G, *_pred, t); |
|
691 |
} |
|
692 |
|
|
693 |
///The distance of a node from the root(s). |
|
694 |
|
|
695 |
///Returns the distance of a node from the root(s). |
|
696 |
///\pre \ref run() must be called before using this function. |
|
697 |
///\warning If node \c v in unreachable from the root(s) the return value |
|
698 |
///of this function is undefined. |
|
699 |
int dist(Node v) const { return (*_dist)[v]; } |
|
700 |
|
|
701 |
///Returns the 'previous arc' of the shortest path tree. |
|
702 |
|
|
703 |
///For a node \c v it returns the 'previous arc' |
|
704 |
///of the shortest path tree, |
|
705 |
///i.e. it returns the last arc of a shortest path from the root(s) to \c |
|
706 |
///v. It is \ref INVALID |
|
707 |
///if \c v is unreachable from the root(s) or \c v is a root. The |
|
708 |
///shortest path tree used here is equal to the shortest path tree used in |
|
709 |
///\ref predNode(). |
|
710 |
///\pre Either \ref run() or \ref start() must be called before using |
|
711 |
///this function. |
|
712 |
Arc predArc(Node v) const { return (*_pred)[v];} |
|
713 |
|
|
714 |
///Returns the 'previous node' of the shortest path tree. |
|
715 |
|
|
716 |
///For a node \c v it returns the 'previous node' |
|
717 |
///of the shortest path tree, |
|
718 |
///i.e. it returns the last but one node from a shortest path from the |
|
719 |
///root(a) to \c /v. |
|
720 |
///It is INVALID if \c v is unreachable from the root(s) or |
|
721 |
///if \c v itself a root. |
|
722 |
///The shortest path tree used here is equal to the shortest path |
|
723 |
///tree used in \ref predArc(). |
|
724 |
///\pre Either \ref run() or \ref start() must be called before |
|
725 |
///using this function. |
|
726 |
Node predNode(Node v) const { return (*_pred)[v]==INVALID ? INVALID: |
|
727 |
G->source((*_pred)[v]); } |
|
728 |
|
|
729 |
///Returns a reference to the NodeMap of distances. |
|
730 |
|
|
731 |
///Returns a reference to the NodeMap of distances. |
|
732 |
///\pre Either \ref run() or \ref init() must |
|
733 |
///be called before using this function. |
|
734 |
const DistMap &distMap() const { return *_dist;} |
|
735 |
|
|
736 |
///Returns a reference to the shortest path tree map. |
|
737 |
|
|
738 |
///Returns a reference to the NodeMap of the arcs of the |
|
739 |
///shortest path tree. |
|
740 |
///\pre Either \ref run() or \ref init() |
|
741 |
///must be called before using this function. |
|
742 |
const PredMap &predMap() const { return *_pred;} |
|
743 |
|
|
744 |
///Checks if a node is reachable from the root. |
|
745 |
|
|
746 |
///Returns \c true if \c v is reachable from the root. |
|
747 |
///\warning The source nodes are indicated as unreached. |
|
748 |
///\pre Either \ref run() or \ref start() |
|
749 |
///must be called before using this function. |
|
750 |
/// |
|
751 |
bool reached(Node v) { return (*_reached)[v]; } |
|
752 |
|
|
753 |
///@} |
|
754 |
}; |
|
755 |
|
|
756 |
///Default traits class of Bfs function. |
|
757 |
|
|
758 |
///Default traits class of Bfs function. |
|
759 |
///\param GR Digraph type. |
|
760 |
template<class GR> |
|
761 |
struct BfsWizardDefaultTraits |
|
762 |
{ |
|
763 |
///The digraph type the algorithm runs on. |
|
764 |
typedef GR Digraph; |
|
765 |
///\brief The type of the map that stores the last |
|
766 |
///arcs of the shortest paths. |
|
767 |
/// |
|
768 |
///The type of the map that stores the last |
|
769 |
///arcs of the shortest paths. |
|
770 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
771 |
/// |
|
772 |
typedef NullMap<typename Digraph::Node,typename GR::Arc> PredMap; |
|
773 |
///Instantiates a PredMap. |
|
774 |
|
|
775 |
///This function instantiates a \ref PredMap. |
|
776 |
///\param g is the digraph, to which we would like to define the PredMap. |
|
777 |
///\todo The digraph alone may be insufficient to initialize |
|
778 |
#ifdef DOXYGEN |
|
779 |
static PredMap *createPredMap(const GR &g) |
|
780 |
#else |
|
781 |
static PredMap *createPredMap(const GR &) |
|
782 |
#endif |
|
783 |
{ |
|
784 |
return new PredMap(); |
|
785 |
} |
|
786 |
|
|
787 |
///The type of the map that indicates which nodes are processed. |
|
788 |
|
|
789 |
///The type of the map that indicates which nodes are processed. |
|
790 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
791 |
///\todo named parameter to set this type, function to read and write. |
|
792 |
typedef NullMap<typename Digraph::Node,bool> ProcessedMap; |
|
793 |
///Instantiates a ProcessedMap. |
|
794 |
|
|
795 |
///This function instantiates a \ref ProcessedMap. |
|
796 |
///\param g is the digraph, to which |
|
797 |
///we would like to define the \ref ProcessedMap |
|
798 |
#ifdef DOXYGEN |
|
799 |
static ProcessedMap *createProcessedMap(const GR &g) |
|
800 |
#else |
|
801 |
static ProcessedMap *createProcessedMap(const GR &) |
|
802 |
#endif |
|
803 |
{ |
|
804 |
return new ProcessedMap(); |
|
805 |
} |
|
806 |
///The type of the map that indicates which nodes are reached. |
|
807 |
|
|
808 |
///The type of the map that indicates which nodes are reached. |
|
809 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
810 |
///\todo named parameter to set this type, function to read and write. |
|
811 |
typedef typename Digraph::template NodeMap<bool> ReachedMap; |
|
812 |
///Instantiates a ReachedMap. |
|
813 |
|
|
814 |
///This function instantiates a \ref ReachedMap. |
|
815 |
///\param G is the digraph, to which |
|
816 |
///we would like to define the \ref ReachedMap. |
|
817 |
static ReachedMap *createReachedMap(const GR &G) |
|
818 |
{ |
|
819 |
return new ReachedMap(G); |
|
820 |
} |
|
821 |
///The type of the map that stores the dists of the nodes. |
|
822 |
|
|
823 |
///The type of the map that stores the dists of the nodes. |
|
824 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
825 |
/// |
|
826 |
typedef NullMap<typename Digraph::Node,int> DistMap; |
|
827 |
///Instantiates a DistMap. |
|
828 |
|
|
829 |
///This function instantiates a \ref DistMap. |
|
830 |
///\param g is the digraph, to which we would like to define the \ref DistMap |
|
831 |
#ifdef DOXYGEN |
|
832 |
static DistMap *createDistMap(const GR &g) |
|
833 |
#else |
|
834 |
static DistMap *createDistMap(const GR &) |
|
835 |
#endif |
|
836 |
{ |
|
837 |
return new DistMap(); |
|
838 |
} |
|
839 |
}; |
|
840 |
|
|
841 |
/// Default traits used by \ref BfsWizard |
|
842 |
|
|
843 |
/// To make it easier to use Bfs algorithm |
|
844 |
///we have created a wizard class. |
|
845 |
/// This \ref BfsWizard class needs default traits, |
|
846 |
///as well as the \ref Bfs class. |
|
847 |
/// The \ref BfsWizardBase is a class to be the default traits of the |
|
848 |
/// \ref BfsWizard class. |
|
849 |
template<class GR> |
|
850 |
class BfsWizardBase : public BfsWizardDefaultTraits<GR> |
|
851 |
{ |
|
852 |
|
|
853 |
typedef BfsWizardDefaultTraits<GR> Base; |
|
854 |
protected: |
|
855 |
/// Type of the nodes in the digraph. |
|
856 |
typedef typename Base::Digraph::Node Node; |
|
857 |
|
|
858 |
/// Pointer to the underlying digraph. |
|
859 |
void *_g; |
|
860 |
///Pointer to the map of reached nodes. |
|
861 |
void *_reached; |
|
862 |
///Pointer to the map of processed nodes. |
|
863 |
void *_processed; |
|
864 |
///Pointer to the map of predecessors arcs. |
|
865 |
void *_pred; |
|
866 |
///Pointer to the map of distances. |
|
867 |
void *_dist; |
|
868 |
///Pointer to the source node. |
|
869 |
Node _source; |
|
870 |
|
|
871 |
public: |
|
872 |
/// Constructor. |
|
873 |
|
|
874 |
/// This constructor does not require parameters, therefore it initiates |
|
875 |
/// all of the attributes to default values (0, INVALID). |
|
876 |
BfsWizardBase() : _g(0), _reached(0), _processed(0), _pred(0), |
|
877 |
_dist(0), _source(INVALID) {} |
|
878 |
|
|
879 |
/// Constructor. |
|
880 |
|
|
881 |
/// This constructor requires some parameters, |
|
882 |
/// listed in the parameters list. |
|
883 |
/// Others are initiated to 0. |
|
884 |
/// \param g is the initial value of \ref _g |
|
885 |
/// \param s is the initial value of \ref _source |
|
886 |
BfsWizardBase(const GR &g, Node s=INVALID) : |
|
887 |
_g(reinterpret_cast<void*>(const_cast<GR*>(&g))), |
|
888 |
_reached(0), _processed(0), _pred(0), _dist(0), _source(s) {} |
|
889 |
|
|
890 |
}; |
|
891 |
|
|
892 |
/// A class to make the usage of Bfs algorithm easier |
|
893 |
|
|
894 |
/// This class is created to make it easier to use Bfs algorithm. |
|
895 |
/// It uses the functions and features of the plain \ref Bfs, |
|
896 |
/// but it is much simpler to use it. |
|
897 |
/// |
|
898 |
/// Simplicity means that the way to change the types defined |
|
899 |
/// in the traits class is based on functions that returns the new class |
|
900 |
/// and not on templatable built-in classes. |
|
901 |
/// When using the plain \ref Bfs |
|
902 |
/// the new class with the modified type comes from |
|
903 |
/// the original class by using the :: |
|
904 |
/// operator. In the case of \ref BfsWizard only |
|
905 |
/// a function have to be called and it will |
|
906 |
/// return the needed class. |
|
907 |
/// |
|
908 |
/// It does not have own \ref run method. When its \ref run method is called |
|
909 |
/// it initiates a plain \ref Bfs class, and calls the \ref Bfs::run |
|
910 |
/// method of it. |
|
911 |
template<class TR> |
|
912 |
class BfsWizard : public TR |
|
913 |
{ |
|
914 |
typedef TR Base; |
|
915 |
|
|
916 |
///The type of the underlying digraph. |
|
917 |
typedef typename TR::Digraph Digraph; |
|
918 |
//\e |
|
919 |
typedef typename Digraph::Node Node; |
|
920 |
//\e |
|
921 |
typedef typename Digraph::NodeIt NodeIt; |
|
922 |
//\e |
|
923 |
typedef typename Digraph::Arc Arc; |
|
924 |
//\e |
|
925 |
typedef typename Digraph::OutArcIt OutArcIt; |
|
926 |
|
|
927 |
///\brief The type of the map that stores |
|
928 |
///the reached nodes |
|
929 |
typedef typename TR::ReachedMap ReachedMap; |
|
930 |
///\brief The type of the map that stores |
|
931 |
///the processed nodes |
|
932 |
typedef typename TR::ProcessedMap ProcessedMap; |
|
933 |
///\brief The type of the map that stores the last |
|
934 |
///arcs of the shortest paths. |
|
935 |
typedef typename TR::PredMap PredMap; |
|
936 |
///The type of the map that stores the dists of the nodes. |
|
937 |
typedef typename TR::DistMap DistMap; |
|
938 |
|
|
939 |
public: |
|
940 |
/// Constructor. |
|
941 |
BfsWizard() : TR() {} |
|
942 |
|
|
943 |
/// Constructor that requires parameters. |
|
944 |
|
|
945 |
/// Constructor that requires parameters. |
|
946 |
/// These parameters will be the default values for the traits class. |
|
947 |
BfsWizard(const Digraph &g, Node s=INVALID) : |
|
948 |
TR(g,s) {} |
|
949 |
|
|
950 |
///Copy constructor |
|
951 |
BfsWizard(const TR &b) : TR(b) {} |
|
952 |
|
|
953 |
~BfsWizard() {} |
|
954 |
|
|
955 |
///Runs Bfs algorithm from a given node. |
|
956 |
|
|
957 |
///Runs Bfs algorithm from a given node. |
|
958 |
///The node can be given by the \ref source function. |
|
959 |
void run() |
|
960 |
{ |
|
961 |
if(Base::_source==INVALID) throw UninitializedParameter(); |
|
962 |
Bfs<Digraph,TR> alg(*reinterpret_cast<const Digraph*>(Base::_g)); |
|
963 |
if(Base::_reached) |
|
964 |
alg.reachedMap(*reinterpret_cast<ReachedMap*>(Base::_reached)); |
|
965 |
if(Base::_processed) |
|
966 |
alg.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed)); |
|
967 |
if(Base::_pred) |
|
968 |
alg.predMap(*reinterpret_cast<PredMap*>(Base::_pred)); |
|
969 |
if(Base::_dist) |
|
970 |
alg.distMap(*reinterpret_cast<DistMap*>(Base::_dist)); |
|
971 |
alg.run(Base::_source); |
|
972 |
} |
|
973 |
|
|
974 |
///Runs Bfs algorithm from the given node. |
|
975 |
|
|
976 |
///Runs Bfs algorithm from the given node. |
|
977 |
///\param s is the given source. |
|
978 |
void run(Node s) |
|
979 |
{ |
|
980 |
Base::_source=s; |
|
981 |
run(); |
|
982 |
} |
|
983 |
|
|
984 |
template<class T> |
|
985 |
struct DefPredMapBase : public Base { |
|
986 |
typedef T PredMap; |
|
987 |
static PredMap *createPredMap(const Digraph &) { return 0; }; |
|
988 |
DefPredMapBase(const TR &b) : TR(b) {} |
|
989 |
}; |
|
990 |
|
|
991 |
///\brief \ref named-templ-param "Named parameter" |
|
992 |
///function for setting PredMap |
|
993 |
/// |
|
994 |
/// \ref named-templ-param "Named parameter" |
|
995 |
///function for setting PredMap |
|
996 |
/// |
|
997 |
template<class T> |
|
998 |
BfsWizard<DefPredMapBase<T> > predMap(const T &t) |
|
999 |
{ |
|
1000 |
Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t)); |
|
1001 |
return BfsWizard<DefPredMapBase<T> >(*this); |
|
1002 |
} |
|
1003 |
|
|
1004 |
|
|
1005 |
template<class T> |
|
1006 |
struct DefReachedMapBase : public Base { |
|
1007 |
typedef T ReachedMap; |
|
1008 |
static ReachedMap *createReachedMap(const Digraph &) { return 0; }; |
|
1009 |
DefReachedMapBase(const TR &b) : TR(b) {} |
|
1010 |
}; |
|
1011 |
|
|
1012 |
///\brief \ref named-templ-param "Named parameter" |
|
1013 |
///function for setting ReachedMap |
|
1014 |
/// |
|
1015 |
/// \ref named-templ-param "Named parameter" |
|
1016 |
///function for setting ReachedMap |
|
1017 |
/// |
|
1018 |
template<class T> |
|
1019 |
BfsWizard<DefReachedMapBase<T> > reachedMap(const T &t) |
|
1020 |
{ |
|
1021 |
Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t)); |
|
1022 |
return BfsWizard<DefReachedMapBase<T> >(*this); |
|
1023 |
} |
|
1024 |
|
|
1025 |
|
|
1026 |
template<class T> |
|
1027 |
struct DefProcessedMapBase : public Base { |
|
1028 |
typedef T ProcessedMap; |
|
1029 |
static ProcessedMap *createProcessedMap(const Digraph &) { return 0; }; |
|
1030 |
DefProcessedMapBase(const TR &b) : TR(b) {} |
|
1031 |
}; |
|
1032 |
|
|
1033 |
///\brief \ref named-templ-param "Named parameter" |
|
1034 |
///function for setting ProcessedMap |
|
1035 |
/// |
|
1036 |
/// \ref named-templ-param "Named parameter" |
|
1037 |
///function for setting ProcessedMap |
|
1038 |
/// |
|
1039 |
template<class T> |
|
1040 |
BfsWizard<DefProcessedMapBase<T> > processedMap(const T &t) |
|
1041 |
{ |
|
1042 |
Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t)); |
|
1043 |
return BfsWizard<DefProcessedMapBase<T> >(*this); |
|
1044 |
} |
|
1045 |
|
|
1046 |
|
|
1047 |
template<class T> |
|
1048 |
struct DefDistMapBase : public Base { |
|
1049 |
typedef T DistMap; |
|
1050 |
static DistMap *createDistMap(const Digraph &) { return 0; }; |
|
1051 |
DefDistMapBase(const TR &b) : TR(b) {} |
|
1052 |
}; |
|
1053 |
|
|
1054 |
///\brief \ref named-templ-param "Named parameter" |
|
1055 |
///function for setting DistMap type |
|
1056 |
/// |
|
1057 |
/// \ref named-templ-param "Named parameter" |
|
1058 |
///function for setting DistMap type |
|
1059 |
/// |
|
1060 |
template<class T> |
|
1061 |
BfsWizard<DefDistMapBase<T> > distMap(const T &t) |
|
1062 |
{ |
|
1063 |
Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t)); |
|
1064 |
return BfsWizard<DefDistMapBase<T> >(*this); |
|
1065 |
} |
|
1066 |
|
|
1067 |
/// Sets the source node, from which the Bfs algorithm runs. |
|
1068 |
|
|
1069 |
/// Sets the source node, from which the Bfs algorithm runs. |
|
1070 |
/// \param s is the source node. |
|
1071 |
BfsWizard<TR> &source(Node s) |
|
1072 |
{ |
|
1073 |
Base::_source=s; |
|
1074 |
return *this; |
|
1075 |
} |
|
1076 |
|
|
1077 |
}; |
|
1078 |
|
|
1079 |
///Function type interface for Bfs algorithm. |
|
1080 |
|
|
1081 |
/// \ingroup search |
|
1082 |
///Function type interface for Bfs algorithm. |
|
1083 |
/// |
|
1084 |
///This function also has several |
|
1085 |
///\ref named-templ-func-param "named parameters", |
|
1086 |
///they are declared as the members of class \ref BfsWizard. |
|
1087 |
///The following |
|
1088 |
///example shows how to use these parameters. |
|
1089 |
///\code |
|
1090 |
/// bfs(g,source).predMap(preds).run(); |
|
1091 |
///\endcode |
|
1092 |
///\warning Don't forget to put the \ref BfsWizard::run() "run()" |
|
1093 |
///to the end of the parameter list. |
|
1094 |
///\sa BfsWizard |
|
1095 |
///\sa Bfs |
|
1096 |
template<class GR> |
|
1097 |
BfsWizard<BfsWizardBase<GR> > |
|
1098 |
bfs(const GR &g,typename GR::Node s=INVALID) |
|
1099 |
{ |
|
1100 |
return BfsWizard<BfsWizardBase<GR> >(g,s); |
|
1101 |
} |
|
1102 |
|
|
1103 |
#ifdef DOXYGEN |
|
1104 |
/// \brief Visitor class for bfs. |
|
1105 |
/// |
|
1106 |
/// This class defines the interface of the BfsVisit events, and |
|
1107 |
/// it could be the base of a real Visitor class. |
|
1108 |
template <typename _Digraph> |
|
1109 |
struct BfsVisitor { |
|
1110 |
typedef _Digraph Digraph; |
|
1111 |
typedef typename Digraph::Arc Arc; |
|
1112 |
typedef typename Digraph::Node Node; |
|
1113 |
/// \brief Called when the arc reach a node. |
|
1114 |
/// |
|
1115 |
/// It is called when the bfs find an arc which target is not |
|
1116 |
/// reached yet. |
|
1117 |
void discover(const Arc& arc) {} |
|
1118 |
/// \brief Called when the node reached first time. |
|
1119 |
/// |
|
1120 |
/// It is Called when the node reached first time. |
|
1121 |
void reach(const Node& node) {} |
|
1122 |
/// \brief Called when the arc examined but target of the arc |
|
1123 |
/// already discovered. |
|
1124 |
/// |
|
1125 |
/// It called when the arc examined but the target of the arc |
|
1126 |
/// already discovered. |
|
1127 |
void examine(const Arc& arc) {} |
|
1128 |
/// \brief Called for the source node of the bfs. |
|
1129 |
/// |
|
1130 |
/// It is called for the source node of the bfs. |
|
1131 |
void start(const Node& node) {} |
|
1132 |
/// \brief Called when the node processed. |
|
1133 |
/// |
|
1134 |
/// It is Called when the node processed. |
|
1135 |
void process(const Node& node) {} |
|
1136 |
}; |
|
1137 |
#else |
|
1138 |
template <typename _Digraph> |
|
1139 |
struct BfsVisitor { |
|
1140 |
typedef _Digraph Digraph; |
|
1141 |
typedef typename Digraph::Arc Arc; |
|
1142 |
typedef typename Digraph::Node Node; |
|
1143 |
void discover(const Arc&) {} |
|
1144 |
void reach(const Node&) {} |
|
1145 |
void examine(const Arc&) {} |
|
1146 |
void start(const Node&) {} |
|
1147 |
void process(const Node&) {} |
|
1148 |
|
|
1149 |
template <typename _Visitor> |
|
1150 |
struct Constraints { |
|
1151 |
void constraints() { |
|
1152 |
Arc arc; |
|
1153 |
Node node; |
|
1154 |
visitor.discover(arc); |
|
1155 |
visitor.reach(node); |
|
1156 |
visitor.examine(arc); |
|
1157 |
visitor.start(node); |
|
1158 |
visitor.process(node); |
|
1159 |
} |
|
1160 |
_Visitor& visitor; |
|
1161 |
}; |
|
1162 |
}; |
|
1163 |
#endif |
|
1164 |
|
|
1165 |
/// \brief Default traits class of BfsVisit class. |
|
1166 |
/// |
|
1167 |
/// Default traits class of BfsVisit class. |
|
1168 |
/// \param _Digraph Digraph type. |
|
1169 |
template<class _Digraph> |
|
1170 |
struct BfsVisitDefaultTraits { |
|
1171 |
|
|
1172 |
/// \brief The digraph type the algorithm runs on. |
|
1173 |
typedef _Digraph Digraph; |
|
1174 |
|
|
1175 |
/// \brief The type of the map that indicates which nodes are reached. |
|
1176 |
/// |
|
1177 |
/// The type of the map that indicates which nodes are reached. |
|
1178 |
/// It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
1179 |
/// \todo named parameter to set this type, function to read and write. |
|
1180 |
typedef typename Digraph::template NodeMap<bool> ReachedMap; |
|
1181 |
|
|
1182 |
/// \brief Instantiates a ReachedMap. |
|
1183 |
/// |
|
1184 |
/// This function instantiates a \ref ReachedMap. |
|
1185 |
/// \param digraph is the digraph, to which |
|
1186 |
/// we would like to define the \ref ReachedMap. |
|
1187 |
static ReachedMap *createReachedMap(const Digraph &digraph) { |
|
1188 |
return new ReachedMap(digraph); |
|
1189 |
} |
|
1190 |
|
|
1191 |
}; |
|
1192 |
|
|
1193 |
/// \ingroup search |
|
1194 |
/// |
|
1195 |
/// \brief %BFS Visit algorithm class. |
|
1196 |
/// |
|
1197 |
/// This class provides an efficient implementation of the %BFS algorithm |
|
1198 |
/// with visitor interface. |
|
1199 |
/// |
|
1200 |
/// The %BfsVisit class provides an alternative interface to the Bfs |
|
1201 |
/// class. It works with callback mechanism, the BfsVisit object calls |
|
1202 |
/// on every bfs event the \c Visitor class member functions. |
|
1203 |
/// |
|
1204 |
/// \param _Digraph The digraph type the algorithm runs on. The default value is |
|
1205 |
/// \ref ListDigraph. The value of _Digraph is not used directly by Bfs, it |
|
1206 |
/// is only passed to \ref BfsDefaultTraits. |
|
1207 |
/// \param _Visitor The Visitor object for the algorithm. The |
|
1208 |
/// \ref BfsVisitor "BfsVisitor<_Digraph>" is an empty Visitor which |
|
1209 |
/// does not observe the Bfs events. If you want to observe the bfs |
|
1210 |
/// events you should implement your own Visitor class. |
|
1211 |
/// \param _Traits Traits class to set various data types used by the |
|
1212 |
/// algorithm. The default traits class is |
|
1213 |
/// \ref BfsVisitDefaultTraits "BfsVisitDefaultTraits<_Digraph>". |
|
1214 |
/// See \ref BfsVisitDefaultTraits for the documentation of |
|
1215 |
/// a Bfs visit traits class. |
|
1216 |
/// |
|
1217 |
/// \author Jacint Szabo, Alpar Juttner and Balazs Dezso |
|
1218 |
#ifdef DOXYGEN |
|
1219 |
template <typename _Digraph, typename _Visitor, typename _Traits> |
|
1220 |
#else |
|
1221 |
template <typename _Digraph = ListDigraph, |
|
1222 |
typename _Visitor = BfsVisitor<_Digraph>, |
|
1223 |
typename _Traits = BfsDefaultTraits<_Digraph> > |
|
1224 |
#endif |
|
1225 |
class BfsVisit { |
|
1226 |
public: |
|
1227 |
|
|
1228 |
/// \brief \ref Exception for uninitialized parameters. |
|
1229 |
/// |
|
1230 |
/// This error represents problems in the initialization |
|
1231 |
/// of the parameters of the algorithms. |
|
1232 |
class UninitializedParameter : public lemon::UninitializedParameter { |
|
1233 |
public: |
|
1234 |
virtual const char* what() const throw() |
|
1235 |
{ |
|
1236 |
return "lemon::BfsVisit::UninitializedParameter"; |
|
1237 |
} |
|
1238 |
}; |
|
1239 |
|
|
1240 |
typedef _Traits Traits; |
|
1241 |
|
|
1242 |
typedef typename Traits::Digraph Digraph; |
|
1243 |
|
|
1244 |
typedef _Visitor Visitor; |
|
1245 |
|
|
1246 |
///The type of the map indicating which nodes are reached. |
|
1247 |
typedef typename Traits::ReachedMap ReachedMap; |
|
1248 |
|
|
1249 |
private: |
|
1250 |
|
|
1251 |
typedef typename Digraph::Node Node; |
|
1252 |
typedef typename Digraph::NodeIt NodeIt; |
|
1253 |
typedef typename Digraph::Arc Arc; |
|
1254 |
typedef typename Digraph::OutArcIt OutArcIt; |
|
1255 |
|
|
1256 |
/// Pointer to the underlying digraph. |
|
1257 |
const Digraph *_digraph; |
|
1258 |
/// Pointer to the visitor object. |
|
1259 |
Visitor *_visitor; |
|
1260 |
///Pointer to the map of reached status of the nodes. |
|
1261 |
ReachedMap *_reached; |
|
1262 |
///Indicates if \ref _reached is locally allocated (\c true) or not. |
|
1263 |
bool local_reached; |
|
1264 |
|
|
1265 |
std::vector<typename Digraph::Node> _list; |
|
1266 |
int _list_front, _list_back; |
|
1267 |
|
|
1268 |
/// \brief Creates the maps if necessary. |
|
1269 |
/// |
|
1270 |
/// Creates the maps if necessary. |
|
1271 |
void create_maps() { |
|
1272 |
if(!_reached) { |
|
1273 |
local_reached = true; |
|
1274 |
_reached = Traits::createReachedMap(*_digraph); |
|
1275 |
} |
|
1276 |
} |
|
1277 |
|
|
1278 |
protected: |
|
1279 |
|
|
1280 |
BfsVisit() {} |
|
1281 |
|
|
1282 |
public: |
|
1283 |
|
|
1284 |
typedef BfsVisit Create; |
|
1285 |
|
|
1286 |
/// \name Named template parameters |
|
1287 |
|
|
1288 |
///@{ |
|
1289 |
template <class T> |
|
1290 |
struct DefReachedMapTraits : public Traits { |
|
1291 |
typedef T ReachedMap; |
|
1292 |
static ReachedMap *createReachedMap(const Digraph &digraph) { |
|
1293 |
throw UninitializedParameter(); |
|
1294 |
} |
|
1295 |
}; |
|
1296 |
/// \brief \ref named-templ-param "Named parameter" for setting |
|
1297 |
/// ReachedMap type |
|
1298 |
/// |
|
1299 |
/// \ref named-templ-param "Named parameter" for setting ReachedMap type |
|
1300 |
template <class T> |
|
1301 |
struct DefReachedMap : public BfsVisit< Digraph, Visitor, |
|
1302 |
DefReachedMapTraits<T> > { |
|
1303 |
typedef BfsVisit< Digraph, Visitor, DefReachedMapTraits<T> > Create; |
|
1304 |
}; |
|
1305 |
///@} |
|
1306 |
|
|
1307 |
public: |
|
1308 |
|
|
1309 |
/// \brief Constructor. |
|
1310 |
/// |
|
1311 |
/// Constructor. |
|
1312 |
/// |
|
1313 |
/// \param digraph the digraph the algorithm will run on. |
|
1314 |
/// \param visitor The visitor of the algorithm. |
|
1315 |
/// |
|
1316 |
BfsVisit(const Digraph& digraph, Visitor& visitor) |
|
1317 |
: _digraph(&digraph), _visitor(&visitor), |
|
1318 |
_reached(0), local_reached(false) {} |
|
1319 |
|
|
1320 |
/// \brief Destructor. |
|
1321 |
/// |
|
1322 |
/// Destructor. |
|
1323 |
~BfsVisit() { |
|
1324 |
if(local_reached) delete _reached; |
|
1325 |
} |
|
1326 |
|
|
1327 |
/// \brief Sets the map indicating if a node is reached. |
|
1328 |
/// |
|
1329 |
/// Sets the map indicating if a node is reached. |
|
1330 |
/// If you don't use this function before calling \ref run(), |
|
1331 |
/// it will allocate one. The destuctor deallocates this |
|
1332 |
/// automatically allocated map, of course. |
|
1333 |
/// \return <tt> (*this) </tt> |
|
1334 |
BfsVisit &reachedMap(ReachedMap &m) { |
|
1335 |
if(local_reached) { |
|
1336 |
delete _reached; |
|
1337 |
local_reached = false; |
|
1338 |
} |
|
1339 |
_reached = &m; |
|
1340 |
return *this; |
|
1341 |
} |
|
1342 |
|
|
1343 |
public: |
|
1344 |
/// \name Execution control |
|
1345 |
/// The simplest way to execute the algorithm is to use |
|
1346 |
/// one of the member functions called \c run(...). |
|
1347 |
/// \n |
|
1348 |
/// If you need more control on the execution, |
|
1349 |
/// first you must call \ref init(), then you can adda source node |
|
1350 |
/// with \ref addSource(). |
|
1351 |
/// Finally \ref start() will perform the actual path |
|
1352 |
/// computation. |
|
1353 |
|
|
1354 |
/// @{ |
|
1355 |
/// \brief Initializes the internal data structures. |
|
1356 |
/// |
|
1357 |
/// Initializes the internal data structures. |
|
1358 |
/// |
|
1359 |
void init() { |
|
1360 |
create_maps(); |
|
1361 |
_list.resize(countNodes(*_digraph)); |
|
1362 |
_list_front = _list_back = -1; |
|
1363 |
for (NodeIt u(*_digraph) ; u != INVALID ; ++u) { |
|
1364 |
_reached->set(u, false); |
|
1365 |
} |
|
1366 |
} |
|
1367 |
|
|
1368 |
/// \brief Adds a new source node. |
|
1369 |
/// |
|
1370 |
/// Adds a new source node to the set of nodes to be processed. |
|
1371 |
void addSource(Node s) { |
|
1372 |
if(!(*_reached)[s]) { |
|
1373 |
_reached->set(s,true); |
|
1374 |
_visitor->start(s); |
|
1375 |
_visitor->reach(s); |
|
1376 |
_list[++_list_back] = s; |
|
1377 |
} |
|
1378 |
} |
|
1379 |
|
|
1380 |
/// \brief Processes the next node. |
|
1381 |
/// |
|
1382 |
/// Processes the next node. |
|
1383 |
/// |
|
1384 |
/// \return The processed node. |
|
1385 |
/// |
|
1386 |
/// \pre The queue must not be empty! |
|
1387 |
Node processNextNode() { |
|
1388 |
Node n = _list[++_list_front]; |
|
1389 |
_visitor->process(n); |
|
1390 |
Arc e; |
|
1391 |
for (_digraph->firstOut(e, n); e != INVALID; _digraph->nextOut(e)) { |
|
1392 |
Node m = _digraph->target(e); |
|
1393 |
if (!(*_reached)[m]) { |
|
1394 |
_visitor->discover(e); |
|
1395 |
_visitor->reach(m); |
|
1396 |
_reached->set(m, true); |
|
1397 |
_list[++_list_back] = m; |
|
1398 |
} else { |
|
1399 |
_visitor->examine(e); |
|
1400 |
} |
|
1401 |
} |
|
1402 |
return n; |
|
1403 |
} |
|
1404 |
|
|
1405 |
/// \brief Processes the next node. |
|
1406 |
/// |
|
1407 |
/// Processes the next node. And checks that the given target node |
|
1408 |
/// is reached. If the target node is reachable from the processed |
|
1409 |
/// node then the reached parameter will be set true. The reached |
|
1410 |
/// parameter should be initially false. |
|
1411 |
/// |
|
1412 |
/// \param target The target node. |
|
1413 |
/// \retval reach Indicates that the target node is reached. |
|
1414 |
/// \return The processed node. |
|
1415 |
/// |
|
1416 |
/// \warning The queue must not be empty! |
|
1417 |
Node processNextNode(Node target, bool& reach) { |
|
1418 |
Node n = _list[++_list_front]; |
|
1419 |
_visitor->process(n); |
|
1420 |
Arc e; |
|
1421 |
for (_digraph->firstOut(e, n); e != INVALID; _digraph->nextOut(e)) { |
|
1422 |
Node m = _digraph->target(e); |
|
1423 |
if (!(*_reached)[m]) { |
|
1424 |
_visitor->discover(e); |
|
1425 |
_visitor->reach(m); |
|
1426 |
_reached->set(m, true); |
|
1427 |
_list[++_list_back] = m; |
|
1428 |
reach = reach || (target == m); |
|
1429 |
} else { |
|
1430 |
_visitor->examine(e); |
|
1431 |
} |
|
1432 |
} |
|
1433 |
return n; |
|
1434 |
} |
|
1435 |
|
|
1436 |
/// \brief Processes the next node. |
|
1437 |
/// |
|
1438 |
/// Processes the next node. And checks that at least one of |
|
1439 |
/// reached node has true value in the \c nm node map. If one node |
|
1440 |
/// with true value is reachable from the processed node then the |
|
1441 |
/// rnode parameter will be set to the first of such nodes. |
|
1442 |
/// |
|
1443 |
/// \param nm The node map of possible targets. |
|
1444 |
/// \retval rnode The reached target node. |
|
1445 |
/// \return The processed node. |
|
1446 |
/// |
|
1447 |
/// \warning The queue must not be empty! |
|
1448 |
template <typename NM> |
|
1449 |
Node processNextNode(const NM& nm, Node& rnode) { |
|
1450 |
Node n = _list[++_list_front]; |
|
1451 |
_visitor->process(n); |
|
1452 |
Arc e; |
|
1453 |
for (_digraph->firstOut(e, n); e != INVALID; _digraph->nextOut(e)) { |
|
1454 |
Node m = _digraph->target(e); |
|
1455 |
if (!(*_reached)[m]) { |
|
1456 |
_visitor->discover(e); |
|
1457 |
_visitor->reach(m); |
|
1458 |
_reached->set(m, true); |
|
1459 |
_list[++_list_back] = m; |
|
1460 |
if (nm[m] && rnode == INVALID) rnode = m; |
|
1461 |
} else { |
|
1462 |
_visitor->examine(e); |
|
1463 |
} |
|
1464 |
} |
|
1465 |
return n; |
|
1466 |
} |
|
1467 |
|
|
1468 |
/// \brief Next node to be processed. |
|
1469 |
/// |
|
1470 |
/// Next node to be processed. |
|
1471 |
/// |
|
1472 |
/// \return The next node to be processed or INVALID if the stack is |
|
1473 |
/// empty. |
|
1474 |
Node nextNode() { |
|
1475 |
return _list_front != _list_back ? _list[_list_front + 1] : INVALID; |
|
1476 |
} |
|
1477 |
|
|
1478 |
/// \brief Returns \c false if there are nodes |
|
1479 |
/// to be processed in the queue |
|
1480 |
/// |
|
1481 |
/// Returns \c false if there are nodes |
|
1482 |
/// to be processed in the queue |
|
1483 |
bool emptyQueue() { return _list_front == _list_back; } |
|
1484 |
|
|
1485 |
/// \brief Returns the number of the nodes to be processed. |
|
1486 |
/// |
|
1487 |
/// Returns the number of the nodes to be processed in the queue. |
|
1488 |
int queueSize() { return _list_back - _list_front; } |
|
1489 |
|
|
1490 |
/// \brief Executes the algorithm. |
|
1491 |
/// |
|
1492 |
/// Executes the algorithm. |
|
1493 |
/// |
|
1494 |
/// \pre init() must be called and at least one node should be added |
|
1495 |
/// with addSource() before using this function. |
|
1496 |
void start() { |
|
1497 |
while ( !emptyQueue() ) processNextNode(); |
|
1498 |
} |
|
1499 |
|
|
1500 |
/// \brief Executes the algorithm until \c dest is reached. |
|
1501 |
/// |
|
1502 |
/// Executes the algorithm until \c dest is reached. |
|
1503 |
/// |
|
1504 |
/// \pre init() must be called and at least one node should be added |
|
1505 |
/// with addSource() before using this function. |
|
1506 |
void start(Node dest) { |
|
1507 |
bool reach = false; |
|
1508 |
while ( !emptyQueue() && !reach ) processNextNode(dest, reach); |
|
1509 |
} |
|
1510 |
|
|
1511 |
/// \brief Executes the algorithm until a condition is met. |
|
1512 |
/// |
|
1513 |
/// Executes the algorithm until a condition is met. |
|
1514 |
/// |
|
1515 |
/// \pre init() must be called and at least one node should be added |
|
1516 |
/// with addSource() before using this function. |
|
1517 |
/// |
|
1518 |
///\param nm must be a bool (or convertible) node map. The |
|
1519 |
///algorithm will stop when it reaches a node \c v with |
|
1520 |
/// <tt>nm[v]</tt> true. |
|
1521 |
/// |
|
1522 |
///\return The reached node \c v with <tt>nm[v]</tt> true or |
|
1523 |
///\c INVALID if no such node was found. |
|
1524 |
template <typename NM> |
|
1525 |
Node start(const NM &nm) { |
|
1526 |
Node rnode = INVALID; |
|
1527 |
while ( !emptyQueue() && rnode == INVALID ) { |
|
1528 |
processNextNode(nm, rnode); |
|
1529 |
} |
|
1530 |
return rnode; |
|
1531 |
} |
|
1532 |
|
|
1533 |
/// \brief Runs %BFSVisit algorithm from node \c s. |
|
1534 |
/// |
|
1535 |
/// This method runs the %BFS algorithm from a root node \c s. |
|
1536 |
/// \note b.run(s) is just a shortcut of the following code. |
|
1537 |
///\code |
|
1538 |
/// b.init(); |
|
1539 |
/// b.addSource(s); |
|
1540 |
/// b.start(); |
|
1541 |
///\endcode |
|
1542 |
void run(Node s) { |
|
1543 |
init(); |
|
1544 |
addSource(s); |
|
1545 |
start(); |
|
1546 |
} |
|
1547 |
|
|
1548 |
/// \brief Runs %BFSVisit algorithm to visit all nodes in the digraph. |
|
1549 |
/// |
|
1550 |
/// This method runs the %BFS algorithm in order to |
|
1551 |
/// compute the %BFS path to each node. The algorithm computes |
|
1552 |
/// - The %BFS tree. |
|
1553 |
/// - The distance of each node from the root in the %BFS tree. |
|
1554 |
/// |
|
1555 |
///\note b.run() is just a shortcut of the following code. |
|
1556 |
///\code |
|
1557 |
/// b.init(); |
|
1558 |
/// for (NodeIt it(digraph); it != INVALID; ++it) { |
|
1559 |
/// if (!b.reached(it)) { |
|
1560 |
/// b.addSource(it); |
|
1561 |
/// b.start(); |
|
1562 |
/// } |
|
1563 |
/// } |
|
1564 |
///\endcode |
|
1565 |
void run() { |
|
1566 |
init(); |
|
1567 |
for (NodeIt it(*_digraph); it != INVALID; ++it) { |
|
1568 |
if (!reached(it)) { |
|
1569 |
addSource(it); |
|
1570 |
start(); |
|
1571 |
} |
|
1572 |
} |
|
1573 |
} |
|
1574 |
///@} |
|
1575 |
|
|
1576 |
/// \name Query Functions |
|
1577 |
/// The result of the %BFS algorithm can be obtained using these |
|
1578 |
/// functions.\n |
|
1579 |
/// Before the use of these functions, |
|
1580 |
/// either run() or start() must be called. |
|
1581 |
///@{ |
|
1582 |
|
|
1583 |
/// \brief Checks if a node is reachable from the root. |
|
1584 |
/// |
|
1585 |
/// Returns \c true if \c v is reachable from the root(s). |
|
1586 |
/// \warning The source nodes are inditated as unreachable. |
|
1587 |
/// \pre Either \ref run() or \ref start() |
|
1588 |
/// must be called before using this function. |
|
1589 |
/// |
|
1590 |
bool reached(Node v) { return (*_reached)[v]; } |
|
1591 |
///@} |
|
1592 |
}; |
|
1593 |
|
|
1594 |
} //END OF NAMESPACE LEMON |
|
1595 |
|
|
1596 |
#endif |
|
1597 |
1 |
/* -*- C++ -*- |
|
2 |
* |
|
3 |
* This file is a part of LEMON, a generic C++ optimization library |
|
4 |
* |
|
5 |
* Copyright (C) 2003-2008 |
|
6 |
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
|
7 |
* (Egervary Research Group on Combinatorial Optimization, EGRES). |
|
8 |
* |
|
9 |
* Permission to use, modify and distribute this software is granted |
|
10 |
* provided that this copyright notice appears in all copies. For |
|
11 |
* precise terms see the accompanying LICENSE file. |
|
12 |
* |
|
13 |
* This software is provided "AS IS" with no warranty of any kind, |
|
14 |
* express or implied, and with no claim as to its suitability for any |
|
15 |
* purpose. |
|
16 |
* |
|
17 |
*/ |
|
18 |
|
|
19 |
#ifndef LEMON_BIN_HEAP_H |
|
20 |
#define LEMON_BIN_HEAP_H |
|
21 |
|
|
22 |
///\ingroup auxdat |
|
23 |
///\file |
|
24 |
///\brief Binary Heap implementation. |
|
25 |
|
|
26 |
#include <vector> |
|
27 |
#include <utility> |
|
28 |
#include <functional> |
|
29 |
|
|
30 |
namespace lemon { |
|
31 |
|
|
32 |
///\ingroup auxdat |
|
33 |
/// |
|
34 |
///\brief A Binary Heap implementation. |
|
35 |
/// |
|
36 |
///This class implements the \e binary \e heap data structure. A \e heap |
|
37 |
///is a data structure for storing items with specified values called \e |
|
38 |
///priorities in such a way that finding the item with minimum priority is |
|
39 |
///efficient. \c Compare specifies the ordering of the priorities. In a heap |
|
40 |
///one can change the priority of an item, add or erase an item, etc. |
|
41 |
/// |
|
42 |
///\param _Prio Type of the priority of the items. |
|
43 |
///\param _ItemIntMap A read and writable Item int map, used internally |
|
44 |
///to handle the cross references. |
|
45 |
///\param _Compare A class for the ordering of the priorities. The |
|
46 |
///default is \c std::less<_Prio>. |
|
47 |
/// |
|
48 |
///\sa FibHeap |
|
49 |
///\sa Dijkstra |
|
50 |
template <typename _Prio, typename _ItemIntMap, |
|
51 |
typename _Compare = std::less<_Prio> > |
|
52 |
class BinHeap { |
|
53 |
|
|
54 |
public: |
|
55 |
///\e |
|
56 |
typedef _ItemIntMap ItemIntMap; |
|
57 |
///\e |
|
58 |
typedef _Prio Prio; |
|
59 |
///\e |
|
60 |
typedef typename ItemIntMap::Key Item; |
|
61 |
///\e |
|
62 |
typedef std::pair<Item,Prio> Pair; |
|
63 |
///\e |
|
64 |
typedef _Compare Compare; |
|
65 |
|
|
66 |
/// \brief Type to represent the items states. |
|
67 |
/// |
|
68 |
/// Each Item element have a state associated to it. It may be "in heap", |
|
69 |
/// "pre heap" or "post heap". The latter two are indifferent from the |
|
70 |
/// heap's point of view, but may be useful to the user. |
|
71 |
/// |
|
72 |
/// The ItemIntMap \e should be initialized in such way that it maps |
|
73 |
/// PRE_HEAP (-1) to any element to be put in the heap... |
|
74 |
enum State { |
|
75 |
IN_HEAP = 0, |
|
76 |
PRE_HEAP = -1, |
|
77 |
POST_HEAP = -2 |
|
78 |
}; |
|
79 |
|
|
80 |
private: |
|
81 |
std::vector<Pair> data; |
|
82 |
Compare comp; |
|
83 |
ItemIntMap &iim; |
|
84 |
|
|
85 |
public: |
|
86 |
/// \brief The constructor. |
|
87 |
/// |
|
88 |
/// The constructor. |
|
89 |
/// \param _iim should be given to the constructor, since it is used |
|
90 |
/// internally to handle the cross references. The value of the map |
|
91 |
/// should be PRE_HEAP (-1) for each element. |
|
92 |
explicit BinHeap(ItemIntMap &_iim) : iim(_iim) {} |
|
93 |
|
|
94 |
/// \brief The constructor. |
|
95 |
/// |
|
96 |
/// The constructor. |
|
97 |
/// \param _iim should be given to the constructor, since it is used |
|
98 |
/// internally to handle the cross references. The value of the map |
|
99 |
/// should be PRE_HEAP (-1) for each element. |
|
100 |
/// |
|
101 |
/// \param _comp The comparator function object. |
|
102 |
BinHeap(ItemIntMap &_iim, const Compare &_comp) |
|
103 |
: iim(_iim), comp(_comp) {} |
|
104 |
|
|
105 |
|
|
106 |
/// The number of items stored in the heap. |
|
107 |
/// |
|
108 |
/// \brief Returns the number of items stored in the heap. |
|
109 |
int size() const { return data.size(); } |
|
110 |
|
|
111 |
/// \brief Checks if the heap stores no items. |
|
112 |
/// |
|
113 |
/// Returns \c true if and only if the heap stores no items. |
|
114 |
bool empty() const { return data.empty(); } |
|
115 |
|
|
116 |
/// \brief Make empty this heap. |
|
117 |
/// |
|
118 |
/// Make empty this heap. It does not change the cross reference map. |
|
119 |
/// If you want to reuse what is not surely empty you should first clear |
|
120 |
/// the heap and after that you should set the cross reference map for |
|
121 |
/// each item to \c PRE_HEAP. |
|
122 |
void clear() { |
|
123 |
data.clear(); |
|
124 |
} |
|
125 |
|
|
126 |
private: |
|
127 |
static int parent(int i) { return (i-1)/2; } |
|
128 |
|
|
129 |
static int second_child(int i) { return 2*i+2; } |
|
130 |
bool less(const Pair &p1, const Pair &p2) const { |
|
131 |
return comp(p1.second, p2.second); |
|
132 |
} |
|
133 |
|
|
134 |
int bubble_up(int hole, Pair p) { |
|
135 |
int par = parent(hole); |
|
136 |
while( hole>0 && less(p,data[par]) ) { |
|
137 |
move(data[par],hole); |
|
138 |
hole = par; |
|
139 |
par = parent(hole); |
|
140 |
} |
|
141 |
move(p, hole); |
|
142 |
return hole; |
|
143 |
} |
|
144 |
|
|
145 |
int bubble_down(int hole, Pair p, int length) { |
|
146 |
int child = second_child(hole); |
|
147 |
while(child < length) { |
|
148 |
if( less(data[child-1], data[child]) ) { |
|
149 |
--child; |
|
150 |
} |
|
151 |
if( !less(data[child], p) ) |
|
152 |
goto ok; |
|
153 |
move(data[child], hole); |
|
154 |
hole = child; |
|
155 |
child = second_child(hole); |
|
156 |
} |
|
157 |
child--; |
|
158 |
if( child<length && less(data[child], p) ) { |
|
159 |
move(data[child], hole); |
|
160 |
hole=child; |
|
161 |
} |
|
162 |
ok: |
|
163 |
move(p, hole); |
|
164 |
return hole; |
|
165 |
} |
|
166 |
|
|
167 |
void move(const Pair &p, int i) { |
|
168 |
data[i] = p; |
|
169 |
iim.set(p.first, i); |
|
170 |
} |
|
171 |
|
|
172 |
public: |
|
173 |
/// \brief Insert a pair of item and priority into the heap. |
|
174 |
/// |
|
175 |
/// Adds \c p.first to the heap with priority \c p.second. |
|
176 |
/// \param p The pair to insert. |
|
177 |
void push(const Pair &p) { |
|
178 |
int n = data.size(); |
|
179 |
data.resize(n+1); |
|
180 |
bubble_up(n, p); |
|
181 |
} |
|
182 |
|
|
183 |
/// \brief Insert an item into the heap with the given heap. |
|
184 |
/// |
|
185 |
/// Adds \c i to the heap with priority \c p. |
|
186 |
/// \param i The item to insert. |
|
187 |
/// \param p The priority of the item. |
|
188 |
void push(const Item &i, const Prio &p) { push(Pair(i,p)); } |
|
189 |
|
|
190 |
/// \brief Returns the item with minimum priority relative to \c Compare. |
|
191 |
/// |
|
192 |
/// This method returns the item with minimum priority relative to \c |
|
193 |
/// Compare. |
|
194 |
/// \pre The heap must be nonempty. |
|
195 |
Item top() const { |
|
196 |
return data[0].first; |
|
197 |
} |
|
198 |
|
|
199 |
/// \brief Returns the minimum priority relative to \c Compare. |
|
200 |
/// |
|
201 |
/// It returns the minimum priority relative to \c Compare. |
|
202 |
/// \pre The heap must be nonempty. |
|
203 |
Prio prio() const { |
|
204 |
return data[0].second; |
|
205 |
} |
|
206 |
|
|
207 |
/// \brief Deletes the item with minimum priority relative to \c Compare. |
|
208 |
/// |
|
209 |
/// This method deletes the item with minimum priority relative to \c |
|
210 |
/// Compare from the heap. |
|
211 |
/// \pre The heap must be non-empty. |
|
212 |
void pop() { |
|
213 |
int n = data.size()-1; |
|
214 |
iim.set(data[0].first, POST_HEAP); |
|
215 |
if (n > 0) { |
|
216 |
bubble_down(0, data[n], n); |
|
217 |
} |
|
218 |
data.pop_back(); |
|
219 |
} |
|
220 |
|
|
221 |
/// \brief Deletes \c i from the heap. |
|
222 |
/// |
|
223 |
/// This method deletes item \c i from the heap. |
|
224 |
/// \param i The item to erase. |
|
225 |
/// \pre The item should be in the heap. |
|
226 |
void erase(const Item &i) { |
|
227 |
int h = iim[i]; |
|
228 |
int n = data.size()-1; |
|
229 |
iim.set(data[h].first, POST_HEAP); |
|
230 |
if( h < n ) { |
|
231 |
if ( bubble_up(h, data[n]) == h) { |
|
232 |
bubble_down(h, data[n], n); |
|
233 |
} |
|
234 |
} |
|
235 |
data.pop_back(); |
|
236 |
} |
|
237 |
|
|
238 |
|
|
239 |
/// \brief Returns the priority of \c i. |
|
240 |
/// |
|
241 |
/// This function returns the priority of item \c i. |
|
242 |
/// \pre \c i must be in the heap. |
|
243 |
/// \param i The item. |
|
244 |
Prio operator[](const Item &i) const { |
|
245 |
int idx = iim[i]; |
|
246 |
return data[idx].second; |
|
247 |
} |
|
248 |
|
|
249 |
/// \brief \c i gets to the heap with priority \c p independently |
|
250 |
/// if \c i was already there. |
|
251 |
/// |
|
252 |
/// This method calls \ref push(\c i, \c p) if \c i is not stored |
|
253 |
/// in the heap and sets the priority of \c i to \c p otherwise. |
|
254 |
/// \param i The item. |
|
255 |
/// \param p The priority. |
|
256 |
void set(const Item &i, const Prio &p) { |
|
257 |
int idx = iim[i]; |
|
258 |
if( idx < 0 ) { |
|
259 |
push(i,p); |
|
260 |
} |
|
261 |
else if( comp(p, data[idx].second) ) { |
|
262 |
bubble_up(idx, Pair(i,p)); |
|
263 |
} |
|
264 |
else { |
|
265 |
bubble_down(idx, Pair(i,p), data.size()); |
|
266 |
} |
|
267 |
} |
|
268 |
|
|
269 |
/// \brief Decreases the priority of \c i to \c p. |
|
270 |
/// |
|
271 |
/// This method decreases the priority of item \c i to \c p. |
|
272 |
/// \pre \c i must be stored in the heap with priority at least \c |
|
273 |
/// p relative to \c Compare. |
|
274 |
/// \param i The item. |
|
275 |
/// \param p The priority. |
|
276 |
void decrease(const Item &i, const Prio &p) { |
|
277 |
int idx = iim[i]; |
|
278 |
bubble_up(idx, Pair(i,p)); |
|
279 |
} |
|
280 |
|
|
281 |
/// \brief Increases the priority of \c i to \c p. |
|
282 |
/// |
|
283 |
/// This method sets the priority of item \c i to \c p. |
|
284 |
/// \pre \c i must be stored in the heap with priority at most \c |
|
285 |
/// p relative to \c Compare. |
|
286 |
/// \param i The item. |
|
287 |
/// \param p The priority. |
|
288 |
void increase(const Item &i, const Prio &p) { |
|
289 |
int idx = iim[i]; |
|
290 |
bubble_down(idx, Pair(i,p), data.size()); |
|
291 |
} |
|
292 |
|
|
293 |
/// \brief Returns if \c item is in, has already been in, or has |
|
294 |
/// never been in the heap. |
|
295 |
/// |
|
296 |
/// This method returns PRE_HEAP if \c item has never been in the |
|
297 |
/// heap, IN_HEAP if it is in the heap at the moment, and POST_HEAP |
|
298 |
/// otherwise. In the latter case it is possible that \c item will |
|
299 |
/// get back to the heap again. |
|
300 |
/// \param i The item. |
|
301 |
State state(const Item &i) const { |
|
302 |
int s = iim[i]; |
|
303 |
if( s>=0 ) |
|
304 |
s=0; |
|
305 |
return State(s); |
|
306 |
} |
|
307 |
|
|
308 |
/// \brief Sets the state of the \c item in the heap. |
|
309 |
/// |
|
310 |
/// Sets the state of the \c item in the heap. It can be used to |
|
311 |
/// manually clear the heap when it is important to achive the |
|
312 |
/// better time complexity. |
|
313 |
/// \param i The item. |
|
314 |
/// \param st The state. It should not be \c IN_HEAP. |
|
315 |
void state(const Item& i, State st) { |
|
316 |
switch (st) { |
|
317 |
case POST_HEAP: |
|
318 |
case PRE_HEAP: |
|
319 |
if (state(i) == IN_HEAP) { |
|
320 |
erase(i); |
|
321 |
} |
|
322 |
iim[i] = st; |
|
323 |
break; |
|
324 |
case IN_HEAP: |
|
325 |
break; |
|
326 |
} |
|
327 |
} |
|
328 |
|
|
329 |
/// \brief Replaces an item in the heap. |
|
330 |
/// |
|
331 |
/// The \c i item is replaced with \c j item. The \c i item should |
|
332 |
/// be in the heap, while the \c j should be out of the heap. The |
|
333 |
/// \c i item will out of the heap and \c j will be in the heap |
|
334 |
/// with the same prioriority as prevoiusly the \c i item. |
|
335 |
void replace(const Item& i, const Item& j) { |
|
336 |
int idx = iim[i]; |
|
337 |
iim.set(i, iim[j]); |
|
338 |
iim.set(j, idx); |
|
339 |
data[idx].first = j; |
|
340 |
} |
|
341 |
|
|
342 |
}; // class BinHeap |
|
343 |
|
|
344 |
} // namespace lemon |
|
345 |
|
|
346 |
#endif // LEMON_BIN_HEAP_H |
1 |
/* -*- C++ -*- |
|
2 |
* |
|
3 |
* This file is a part of LEMON, a generic C++ optimization library |
|
4 |
* |
|
5 |
* Copyright (C) 2003-2008 |
|
6 |
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
|
7 |
* (Egervary Research Group on Combinatorial Optimization, EGRES). |
|
8 |
* |
|
9 |
* Permission to use, modify and distribute this software is granted |
|
10 |
* provided that this copyright notice appears in all copies. For |
|
11 |
* precise terms see the accompanying LICENSE file. |
|
12 |
* |
|
13 |
* This software is provided "AS IS" with no warranty of any kind, |
|
14 |
* express or implied, and with no claim as to its suitability for any |
|
15 |
* purpose. |
|
16 |
* |
|
17 |
*/ |
|
18 |
|
|
19 |
#ifndef LEMON_BITS_PRED_MAP_PATH_H |
|
20 |
#define LEMON_BITS_PRED_MAP_PATH_H |
|
21 |
|
|
22 |
namespace lemon { |
|
23 |
|
|
24 |
template <typename _Digraph, typename _PredMap> |
|
25 |
class PredMapPath { |
|
26 |
public: |
|
27 |
typedef True RevPathTag; |
|
28 |
|
|
29 |
typedef _Digraph Digraph; |
|
30 |
typedef typename Digraph::Arc Arc; |
|
31 |
typedef _PredMap PredMap; |
|
32 |
|
|
33 |
PredMapPath(const Digraph& _digraph, const PredMap& _predMap, |
|
34 |
typename Digraph::Node _target) |
|
35 |
: digraph(_digraph), predMap(_predMap), target(_target) {} |
|
36 |
|
|
37 |
int length() const { |
|
38 |
int len = 0; |
|
39 |
typename Digraph::Node node = target; |
|
40 |
typename Digraph::Arc arc; |
|
41 |
while ((arc = predMap[node]) != INVALID) { |
|
42 |
node = digraph.source(arc); |
|
43 |
++len; |
|
44 |
} |
|
45 |
return len; |
|
46 |
} |
|
47 |
|
|
48 |
bool empty() const { |
|
49 |
return predMap[target] != INVALID; |
|
50 |
} |
|
51 |
|
|
52 |
class RevArcIt { |
|
53 |
public: |
|
54 |
RevArcIt() {} |
|
55 |
RevArcIt(Invalid) : path(0), current(INVALID) {} |
|
56 |
RevArcIt(const PredMapPath& _path) |
|
57 |
: path(&_path), current(_path.target) { |
|
58 |
if (path->predMap[current] == INVALID) current = INVALID; |
|
59 |
} |
|
60 |
|
|
61 |
operator const typename Digraph::Arc() const { |
|
62 |
return path->predMap[current]; |
|
63 |
} |
|
64 |
|
|
65 |
RevArcIt& operator++() { |
|
66 |
current = path->digraph.source(path->predMap[current]); |
|
67 |
if (path->predMap[current] == INVALID) current = INVALID; |
|
68 |
return *this; |
|
69 |
} |
|
70 |
|
|
71 |
bool operator==(const RevArcIt& e) const { |
|
72 |
return current == e.current; |
|
73 |
} |
|
74 |
|
|
75 |
bool operator!=(const RevArcIt& e) const { |
|
76 |
return current != e.current; |
|
77 |
} |
|
78 |
|
|
79 |
bool operator<(const RevArcIt& e) const { |
|
80 |
return current < e.current; |
|
81 |
} |
|
82 |
|
|
83 |
private: |
|
84 |
const PredMapPath* path; |
|
85 |
typename Digraph::Node current; |
|
86 |
}; |
|
87 |
|
|
88 |
private: |
|
89 |
const Digraph& digraph; |
|
90 |
const PredMap& predMap; |
|
91 |
typename Digraph::Node target; |
|
92 |
}; |
|
93 |
|
|
94 |
|
|
95 |
template <typename _Digraph, typename _PredMatrixMap> |
|
96 |
class PredMatrixMapPath { |
|
97 |
public: |
|
98 |
typedef True RevPathTag; |
|
99 |
|
|
100 |
typedef _Digraph Digraph; |
|
101 |
typedef typename Digraph::Arc Arc; |
|
102 |
typedef _PredMatrixMap PredMatrixMap; |
|
103 |
|
|
104 |
PredMatrixMapPath(const Digraph& _digraph, |
|
105 |
const PredMatrixMap& _predMatrixMap, |
|
106 |
typename Digraph::Node _source, |
|
107 |
typename Digraph::Node _target) |
|
108 |
: digraph(_digraph), predMatrixMap(_predMatrixMap), |
|
109 |
source(_source), target(_target) {} |
|
110 |
|
|
111 |
int length() const { |
|
112 |
int len = 0; |
|
113 |
typename Digraph::Node node = target; |
|
114 |
typename Digraph::Arc arc; |
|
115 |
while ((arc = predMatrixMap(source, node)) != INVALID) { |
|
116 |
node = digraph.source(arc); |
|
117 |
++len; |
|
118 |
} |
|
119 |
return len; |
|
120 |
} |
|
121 |
|
|
122 |
bool empty() const { |
|
123 |
return source != target; |
|
124 |
} |
|
125 |
|
|
126 |
class RevArcIt { |
|
127 |
public: |
|
128 |
RevArcIt() {} |
|
129 |
RevArcIt(Invalid) : path(0), current(INVALID) {} |
|
130 |
RevArcIt(const PredMatrixMapPath& _path) |
|
131 |
: path(&_path), current(_path.target) { |
|
132 |
if (path->predMatrixMap(path->source, current) == INVALID) |
|
133 |
current = INVALID; |
|
134 |
} |
|
135 |
|
|
136 |
operator const typename Digraph::Arc() const { |
|
137 |
return path->predMatrixMap(path->source, current); |
|
138 |
} |
|
139 |
|
|
140 |
RevArcIt& operator++() { |
|
141 |
current = |
|
142 |
path->digraph.source(path->predMatrixMap(path->source, current)); |
|
143 |
if (path->predMatrixMap(path->source, current) == INVALID) |
|
144 |
current = INVALID; |
|
145 |
return *this; |
|
146 |
} |
|
147 |
|
|
148 |
bool operator==(const RevArcIt& e) const { |
|
149 |
return current == e.current; |
|
150 |
} |
|
151 |
|
|
152 |
bool operator!=(const RevArcIt& e) const { |
|
153 |
return current != e.current; |
|
154 |
} |
|
155 |
|
|
156 |
bool operator<(const RevArcIt& e) const { |
|
157 |
return current < e.current; |
|
158 |
} |
|
159 |
|
|
160 |
private: |
|
161 |
const PredMatrixMapPath* path; |
|
162 |
typename Digraph::Node current; |
|
163 |
}; |
|
164 |
|
|
165 |
private: |
|
166 |
const Digraph& digraph; |
|
167 |
const PredMatrixMap& predMatrixMap; |
|
168 |
typename Digraph::Node source; |
|
169 |
typename Digraph::Node target; |
|
170 |
}; |
|
171 |
|
|
172 |
} |
|
173 |
|
|
174 |
#endif |
1 |
/* -*- C++ -*- |
|
2 |
* |
|
3 |
* This file is a part of LEMON, a generic C++ optimization library |
|
4 |
* |
|
5 |
* Copyright (C) 2003-2008 |
|
6 |
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
|
7 |
* (Egervary Research Group on Combinatorial Optimization, EGRES). |
|
8 |
* |
|
9 |
* Permission to use, modify and distribute this software is granted |
|
10 |
* provided that this copyright notice appears in all copies. For |
|
11 |
* precise terms see the accompanying LICENSE file. |
|
12 |
* |
|
13 |
* This software is provided "AS IS" with no warranty of any kind, |
|
14 |
* express or implied, and with no claim as to its suitability for any |
|
15 |
* purpose. |
|
16 |
* |
|
17 |
*/ |
|
18 |
|
|
19 |
///\ingroup concept |
|
20 |
///\file |
|
21 |
///\brief Classes for representing heaps. |
|
22 |
/// |
|
23 |
|
|
24 |
#ifndef LEMON_CONCEPT_HEAP_H |
|
25 |
#define LEMON_CONCEPT_HEAP_H |
|
26 |
|
|
27 |
#include <lemon/bits/invalid.h> |
|
28 |
|
|
29 |
namespace lemon { |
|
30 |
namespace concepts { |
|
31 |
/// \addtogroup concept |
|
32 |
/// @{ |
|
33 |
|
|
34 |
|
|
35 |
/// \brief A concept structure describes the main interface of heaps. |
|
36 |
/// |
|
37 |
/// A concept structure describes the main interface of heaps. |
|
38 |
/// |
|
39 |
template <typename Prio, typename ItemIntMap> |
|
40 |
class Heap { |
|
41 |
public: |
|
42 |
|
|
43 |
///\brief Type of the items stored in the heap. |
|
44 |
typedef typename ItemIntMap::Key Item; |
|
45 |
|
|
46 |
|
|
47 |
/// \brief Type to represent the items states. |
|
48 |
/// |
|
49 |
/// Each Item element have a state associated to it. It may be "in heap", |
|
50 |
/// "pre heap" or "post heap". The later two are indifferent from the |
|
51 |
/// heap's point of view, but may be useful to the user. |
|
52 |
/// |
|
53 |
/// The ItemIntMap _should_ be initialized in such way, that it maps |
|
54 |
/// PRE_HEAP (-1) to any element to be put in the heap... |
|
55 |
enum State { |
|
56 |
IN_HEAP = 0, |
|
57 |
PRE_HEAP = -1, |
|
58 |
POST_HEAP = -2 |
|
59 |
}; |
|
60 |
|
|
61 |
/// \brief The constructor. |
|
62 |
/// |
|
63 |
/// The constructor. |
|
64 |
/// \param _iim should be given to the constructor, since it is used |
|
65 |
/// internally to handle the cross references. The value of the map |
|
66 |
/// should be PRE_HEAP (-1) for each element. |
|
67 |
explicit Heap(ItemIntMap &_iim) {} |
|
68 |
|
|
69 |
/// \brief The number of items stored in the heap. |
|
70 |
/// |
|
71 |
/// Returns the number of items stored in the heap. |
|
72 |
int size() const { return 0; } |
|
73 |
|
|
74 |
/// \brief Checks if the heap stores no items. |
|
75 |
/// |
|
76 |
/// Returns \c true if and only if the heap stores no items. |
|
77 |
bool empty() const { return false; } |
|
78 |
|
|
79 |
/// \brief Makes empty this heap. |
|
80 |
/// |
|
81 |
/// Makes this heap empty. |
|
82 |
void clear(); |
|
83 |
|
|
84 |
/// \brief Insert an item into the heap with the given heap. |
|
85 |
/// |
|
86 |
/// Adds \c i to the heap with priority \c p. |
|
87 |
/// \param i The item to insert. |
|
88 |
/// \param p The priority of the item. |
|
89 |
void push(const Item &i, const Prio &p) {} |
|
90 |
|
|
91 |
/// \brief Returns the item with minimum priority. |
|
92 |
/// |
|
93 |
/// This method returns the item with minimum priority. |
|
94 |
/// \pre The heap must be nonempty. |
|
95 |
Item top() const {} |
|
96 |
|
|
97 |
/// \brief Returns the minimum priority. |
|
98 |
/// |
|
99 |
/// It returns the minimum priority. |
|
100 |
/// \pre The heap must be nonempty. |
|
101 |
Prio prio() const {} |
|
102 |
|
|
103 |
/// \brief Deletes the item with minimum priority. |
|
104 |
/// |
|
105 |
/// This method deletes the item with minimum priority. |
|
106 |
/// \pre The heap must be non-empty. |
|
107 |
void pop() {} |
|
108 |
|
|
109 |
/// \brief Deletes \c i from the heap. |
|
110 |
/// |
|
111 |
/// This method deletes item \c i from the heap, if \c i was |
|
112 |
/// already stored in the heap. |
|
113 |
/// \param i The item to erase. |
|
114 |
void erase(const Item &i) {} |
|
115 |
|
|
116 |
/// \brief Returns the priority of \c i. |
|
117 |
/// |
|
118 |
/// This function returns the priority of item \c i. |
|
119 |
/// \pre \c i must be in the heap. |
|
120 |
/// \param i The item. |
|
121 |
Prio operator[](const Item &i) const {} |
|
122 |
|
|
123 |
/// \brief \c i gets to the heap with priority \c p independently |
|
124 |
/// if \c i was already there. |
|
125 |
/// |
|
126 |
/// This method calls \ref push(\c i, \c p) if \c i is not stored |
|
127 |
/// in the heap and sets the priority of \c i to \c p otherwise. |
|
128 |
/// It may throw an \e UnderFlowPriorityException. |
|
129 |
/// \param i The item. |
|
130 |
/// \param p The priority. |
|
131 |
void set(const Item &i, const Prio &p) {} |
|
132 |
|
|
133 |
/// \brief Decreases the priority of \c i to \c p. |
|
134 |
/// |
|
135 |
/// This method decreases the priority of item \c i to \c p. |
|
136 |
/// \pre \c i must be stored in the heap with priority at least \c p. |
|
137 |
/// \param i The item. |
|
138 |
/// \param p The priority. |
|
139 |
void decrease(const Item &i, const Prio &p) {} |
|
140 |
|
|
141 |
/// \brief Increases the priority of \c i to \c p. |
|
142 |
/// |
|
143 |
/// This method sets the priority of item \c i to \c p. |
|
144 |
/// \pre \c i must be stored in the heap with priority at most \c |
|
145 |
/// p relative to \c Compare. |
|
146 |
/// \param i The item. |
|
147 |
/// \param p The priority. |
|
148 |
void increase(const Item &i, const Prio &p) {} |
|
149 |
|
|
150 |
/// \brief Returns if \c item is in, has already been in, or has |
|
151 |
/// never been in the heap. |
|
152 |
/// |
|
153 |
/// This method returns PRE_HEAP if \c item has never been in the |
|
154 |
/// heap, IN_HEAP if it is in the heap at the moment, and POST_HEAP |
|
155 |
/// otherwise. In the latter case it is possible that \c item will |
|
156 |
/// get back to the heap again. |
|
157 |
/// \param i The item. |
|
158 |
State state(const Item &i) const {} |
|
159 |
|
|
160 |
/// \brief Sets the state of the \c item in the heap. |
|
161 |
/// |
|
162 |
/// Sets the state of the \c item in the heap. It can be used to |
|
163 |
/// manually clear the heap when it is important to achive the |
|
164 |
/// better time complexity. |
|
165 |
/// \param i The item. |
|
166 |
/// \param st The state. It should not be \c IN_HEAP. |
|
167 |
void state(const Item& i, State st) {} |
|
168 |
|
|
169 |
|
|
170 |
template <typename _Heap> |
|
171 |
struct Constraints { |
|
172 |
public: |
|
173 |
|
|
174 |
void constraints() { |
|
175 |
Item item; |
|
176 |
Prio prio; |
|
177 |
|
|
178 |
item=Item(); |
|
179 |
prio=Prio(); |
|
180 |
|
|
181 |
ignore_unused_variable_warning(item); |
|
182 |
ignore_unused_variable_warning(prio); |
|
183 |
|
|
184 |
typedef typename _Heap::State State; |
|
185 |
State state; |
|
186 |
|
|
187 |
ignore_unused_variable_warning(state); |
|
188 |
|
|
189 |
_Heap heap1 = _Heap(map); |
|
190 |
|
|
191 |
ignore_unused_variable_warning(heap1); |
|
192 |
|
|
193 |
heap.push(item, prio); |
|
194 |
|
|
195 |
prio = heap.prio(); |
|
196 |
item = heap.top(); |
|
197 |
|
|
198 |
heap.pop(); |
|
199 |
|
|
200 |
heap.set(item, prio); |
|
201 |
heap.decrease(item, prio); |
|
202 |
heap.increase(item, prio); |
|
203 |
prio = heap[item]; |
|
204 |
|
|
205 |
heap.erase(item); |
|
206 |
|
|
207 |
state = heap.state(item); |
|
208 |
|
|
209 |
state = _Heap::PRE_HEAP; |
|
210 |
state = _Heap::IN_HEAP; |
|
211 |
state = _Heap::POST_HEAP; |
|
212 |
|
|
213 |
heap.clear(); |
|
214 |
} |
|
215 |
|
|
216 |
_Heap& heap; |
|
217 |
ItemIntMap& map; |
|
218 |
|
|
219 |
Constraints() : heap(0), map(0) {} |
|
220 |
}; |
|
221 |
}; |
|
222 |
|
|
223 |
/// @} |
|
224 |
} // namespace lemon |
|
225 |
} |
|
226 |
#endif // LEMON_CONCEPT_PATH_H |
1 |
/* -*- C++ -*- |
|
2 |
* |
|
3 |
* This file is a part of LEMON, a generic C++ optimization library |
|
4 |
* |
|
5 |
* Copyright (C) 2003-2008 |
|
6 |
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
|
7 |
* (Egervary Research Group on Combinatorial Optimization, EGRES). |
|
8 |
* |
|
9 |
* Permission to use, modify and distribute this software is granted |
|
10 |
* provided that this copyright notice appears in all copies. For |
|
11 |
* precise terms see the accompanying LICENSE file. |
|
12 |
* |
|
13 |
* This software is provided "AS IS" with no warranty of any kind, |
|
14 |
* express or implied, and with no claim as to its suitability for any |
|
15 |
* purpose. |
|
16 |
* |
|
17 |
*/ |
|
18 |
|
|
19 |
#ifndef LEMON_DFS_H |
|
20 |
#define LEMON_DFS_H |
|
21 |
|
|
22 |
///\ingroup search |
|
23 |
///\file |
|
24 |
///\brief Dfs algorithm. |
|
25 |
|
|
26 |
#include <lemon/list_graph.h> |
|
27 |
#include <lemon/graph_utils.h> |
|
28 |
#include <lemon/bits/path_dump.h> |
|
29 |
#include <lemon/bits/invalid.h> |
|
30 |
#include <lemon/error.h> |
|
31 |
#include <lemon/maps.h> |
|
32 |
|
|
33 |
#include <lemon/concept_check.h> |
|
34 |
|
|
35 |
namespace lemon { |
|
36 |
|
|
37 |
|
|
38 |
///Default traits class of Dfs class. |
|
39 |
|
|
40 |
///Default traits class of Dfs class. |
|
41 |
///\param GR Digraph type. |
|
42 |
template<class GR> |
|
43 |
struct DfsDefaultTraits |
|
44 |
{ |
|
45 |
///The digraph type the algorithm runs on. |
|
46 |
typedef GR Digraph; |
|
47 |
///\brief The type of the map that stores the last |
|
48 |
///arcs of the %DFS paths. |
|
49 |
/// |
|
50 |
///The type of the map that stores the last |
|
51 |
///arcs of the %DFS paths. |
|
52 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
53 |
/// |
|
54 |
typedef typename Digraph::template NodeMap<typename GR::Arc> PredMap; |
|
55 |
///Instantiates a PredMap. |
|
56 |
|
|
57 |
///This function instantiates a \ref PredMap. |
|
58 |
///\param G is the digraph, to which we would like to define the PredMap. |
|
59 |
///\todo The digraph alone may be insufficient to initialize |
|
60 |
static PredMap *createPredMap(const GR &G) |
|
61 |
{ |
|
62 |
return new PredMap(G); |
|
63 |
} |
|
64 |
|
|
65 |
///The type of the map that indicates which nodes are processed. |
|
66 |
|
|
67 |
///The type of the map that indicates which nodes are processed. |
|
68 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
69 |
///\todo named parameter to set this type, function to read and write. |
|
70 |
typedef NullMap<typename Digraph::Node,bool> ProcessedMap; |
|
71 |
///Instantiates a ProcessedMap. |
|
72 |
|
|
73 |
///This function instantiates a \ref ProcessedMap. |
|
74 |
///\param g is the digraph, to which |
|
75 |
///we would like to define the \ref ProcessedMap |
|
76 |
#ifdef DOXYGEN |
|
77 |
static ProcessedMap *createProcessedMap(const GR &g) |
|
78 |
#else |
|
79 |
static ProcessedMap *createProcessedMap(const GR &) |
|
80 |
#endif |
|
81 |
{ |
|
82 |
return new ProcessedMap(); |
|
83 |
} |
|
84 |
///The type of the map that indicates which nodes are reached. |
|
85 |
|
|
86 |
///The type of the map that indicates which nodes are reached. |
|
87 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
88 |
///\todo named parameter to set this type, function to read and write. |
|
89 |
typedef typename Digraph::template NodeMap<bool> ReachedMap; |
|
90 |
///Instantiates a ReachedMap. |
|
91 |
|
|
92 |
///This function instantiates a \ref ReachedMap. |
|
93 |
///\param G is the digraph, to which |
|
94 |
///we would like to define the \ref ReachedMap. |
|
95 |
static ReachedMap *createReachedMap(const GR &G) |
|
96 |
{ |
|
97 |
return new ReachedMap(G); |
|
98 |
} |
|
99 |
///The type of the map that stores the dists of the nodes. |
|
100 |
|
|
101 |
///The type of the map that stores the dists of the nodes. |
|
102 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
103 |
/// |
|
104 |
typedef typename Digraph::template NodeMap<int> DistMap; |
|
105 |
///Instantiates a DistMap. |
|
106 |
|
|
107 |
///This function instantiates a \ref DistMap. |
|
108 |
///\param G is the digraph, to which we would like to define the \ref DistMap |
|
109 |
static DistMap *createDistMap(const GR &G) |
|
110 |
{ |
|
111 |
return new DistMap(G); |
|
112 |
} |
|
113 |
}; |
|
114 |
|
|
115 |
///%DFS algorithm class. |
|
116 |
|
|
117 |
///\ingroup search |
|
118 |
///This class provides an efficient implementation of the %DFS algorithm. |
|
119 |
/// |
|
120 |
///\param GR The digraph type the algorithm runs on. The default value is |
|
121 |
///\ref ListDigraph. The value of GR is not used directly by Dfs, it |
|
122 |
///is only passed to \ref DfsDefaultTraits. |
|
123 |
///\param TR Traits class to set various data types used by the algorithm. |
|
124 |
///The default traits class is |
|
125 |
///\ref DfsDefaultTraits "DfsDefaultTraits<GR>". |
|
126 |
///See \ref DfsDefaultTraits for the documentation of |
|
127 |
///a Dfs traits class. |
|
128 |
/// |
|
129 |
///\author Jacint Szabo and Alpar Juttner |
|
130 |
#ifdef DOXYGEN |
|
131 |
template <typename GR, |
|
132 |
typename TR> |
|
133 |
#else |
|
134 |
template <typename GR=ListDigraph, |
|
135 |
typename TR=DfsDefaultTraits<GR> > |
|
136 |
#endif |
|
137 |
class Dfs { |
|
138 |
public: |
|
139 |
/** |
|
140 |
* \brief \ref Exception for uninitialized parameters. |
|
141 |
* |
|
142 |
* This error represents problems in the initialization |
|
143 |
* of the parameters of the algorithms. |
|
144 |
*/ |
|
145 |
class UninitializedParameter : public lemon::UninitializedParameter { |
|
146 |
public: |
|
147 |
virtual const char* what() const throw() { |
|
148 |
return "lemon::Dfs::UninitializedParameter"; |
|
149 |
} |
|
150 |
}; |
|
151 |
|
|
152 |
typedef TR Traits; |
|
153 |
///The type of the underlying digraph. |
|
154 |
typedef typename TR::Digraph Digraph; |
|
155 |
///\e |
|
156 |
typedef typename Digraph::Node Node; |
|
157 |
///\e |
|
158 |
typedef typename Digraph::NodeIt NodeIt; |
|
159 |
///\e |
|
160 |
typedef typename Digraph::Arc Arc; |
|
161 |
///\e |
|
162 |
typedef typename Digraph::OutArcIt OutArcIt; |
|
163 |
|
|
164 |
///\brief The type of the map that stores the last |
|
165 |
///arcs of the %DFS paths. |
|
166 |
typedef typename TR::PredMap PredMap; |
|
167 |
///The type of the map indicating which nodes are reached. |
|
168 |
typedef typename TR::ReachedMap ReachedMap; |
|
169 |
///The type of the map indicating which nodes are processed. |
|
170 |
typedef typename TR::ProcessedMap ProcessedMap; |
|
171 |
///The type of the map that stores the dists of the nodes. |
|
172 |
typedef typename TR::DistMap DistMap; |
|
173 |
private: |
|
174 |
/// Pointer to the underlying digraph. |
|
175 |
const Digraph *G; |
|
176 |
///Pointer to the map of predecessors arcs. |
|
177 |
PredMap *_pred; |
|
178 |
///Indicates if \ref _pred is locally allocated (\c true) or not. |
|
179 |
bool local_pred; |
|
180 |
///Pointer to the map of distances. |
|
181 |
DistMap *_dist; |
|
182 |
///Indicates if \ref _dist is locally allocated (\c true) or not. |
|
183 |
bool local_dist; |
|
184 |
///Pointer to the map of reached status of the nodes. |
|
185 |
ReachedMap *_reached; |
|
186 |
///Indicates if \ref _reached is locally allocated (\c true) or not. |
|
187 |
bool local_reached; |
|
188 |
///Pointer to the map of processed status of the nodes. |
|
189 |
ProcessedMap *_processed; |
|
190 |
///Indicates if \ref _processed is locally allocated (\c true) or not. |
|
191 |
bool local_processed; |
|
192 |
|
|
193 |
std::vector<typename Digraph::OutArcIt> _stack; |
|
194 |
int _stack_head; |
|
195 |
|
|
196 |
///Creates the maps if necessary. |
|
197 |
|
|
198 |
///\todo Better memory allocation (instead of new). |
|
199 |
void create_maps() |
|
200 |
{ |
|
201 |
if(!_pred) { |
|
202 |
local_pred = true; |
|
203 |
_pred = Traits::createPredMap(*G); |
|
204 |
} |
|
205 |
if(!_dist) { |
|
206 |
local_dist = true; |
|
207 |
_dist = Traits::createDistMap(*G); |
|
208 |
} |
|
209 |
if(!_reached) { |
|
210 |
local_reached = true; |
|
211 |
_reached = Traits::createReachedMap(*G); |
|
212 |
} |
|
213 |
if(!_processed) { |
|
214 |
local_processed = true; |
|
215 |
_processed = Traits::createProcessedMap(*G); |
|
216 |
} |
|
217 |
} |
|
218 |
|
|
219 |
protected: |
|
220 |
|
|
221 |
Dfs() {} |
|
222 |
|
|
223 |
public: |
|
224 |
|
|
225 |
typedef Dfs Create; |
|
226 |
|
|
227 |
///\name Named template parameters |
|
228 |
|
|
229 |
///@{ |
|
230 |
|
|
231 |
template <class T> |
|
232 |
struct DefPredMapTraits : public Traits { |
|
233 |
typedef T PredMap; |
|
234 |
static PredMap *createPredMap(const Digraph &G) |
|
235 |
{ |
|
236 |
throw UninitializedParameter(); |
|
237 |
} |
|
238 |
}; |
|
239 |
///\brief \ref named-templ-param "Named parameter" for setting |
|
240 |
///PredMap type |
|
241 |
/// |
|
242 |
///\ref named-templ-param "Named parameter" for setting PredMap type |
|
243 |
/// |
|
244 |
template <class T> |
|
245 |
struct DefPredMap : public Dfs<Digraph, DefPredMapTraits<T> > { |
|
246 |
typedef Dfs<Digraph, DefPredMapTraits<T> > Create; |
|
247 |
}; |
|
248 |
|
|
249 |
|
|
250 |
template <class T> |
|
251 |
struct DefDistMapTraits : public Traits { |
|
252 |
typedef T DistMap; |
|
253 |
static DistMap *createDistMap(const Digraph &) |
|
254 |
{ |
|
255 |
throw UninitializedParameter(); |
|
256 |
} |
|
257 |
}; |
|
258 |
///\brief \ref named-templ-param "Named parameter" for setting |
|
259 |
///DistMap type |
|
260 |
/// |
|
261 |
///\ref named-templ-param "Named parameter" for setting DistMap |
|
262 |
///type |
|
263 |
template <class T> |
|
264 |
struct DefDistMap { |
|
265 |
typedef Dfs<Digraph, DefDistMapTraits<T> > Create; |
|
266 |
}; |
|
267 |
|
|
268 |
template <class T> |
|
269 |
struct DefReachedMapTraits : public Traits { |
|
270 |
typedef T ReachedMap; |
|
271 |
static ReachedMap *createReachedMap(const Digraph &) |
|
272 |
{ |
|
273 |
throw UninitializedParameter(); |
|
274 |
} |
|
275 |
}; |
|
276 |
///\brief \ref named-templ-param "Named parameter" for setting |
|
277 |
///ReachedMap type |
|
278 |
/// |
|
279 |
///\ref named-templ-param "Named parameter" for setting ReachedMap type |
|
280 |
/// |
|
281 |
template <class T> |
|
282 |
struct DefReachedMap : public Dfs< Digraph, DefReachedMapTraits<T> > { |
|
283 |
typedef Dfs< Digraph, DefReachedMapTraits<T> > Create; |
|
284 |
}; |
|
285 |
|
|
286 |
template <class T> |
|
287 |
struct DefProcessedMapTraits : public Traits { |
|
288 |
typedef T ProcessedMap; |
|
289 |
static ProcessedMap *createProcessedMap(const Digraph &) |
|
290 |
{ |
|
291 |
throw UninitializedParameter(); |
|
292 |
} |
|
293 |
}; |
|
294 |
///\brief \ref named-templ-param "Named parameter" for setting |
|
295 |
///ProcessedMap type |
|
296 |
/// |
|
297 |
///\ref named-templ-param "Named parameter" for setting ProcessedMap type |
|
298 |
/// |
|
299 |
template <class T> |
|
300 |
struct DefProcessedMap : public Dfs< Digraph, DefProcessedMapTraits<T> > { |
|
301 |
typedef Dfs< Digraph, DefProcessedMapTraits<T> > Create; |
|
302 |
}; |
|
303 |
|
|
304 |
struct DefDigraphProcessedMapTraits : public Traits { |
|
305 |
typedef typename Digraph::template NodeMap<bool> ProcessedMap; |
|
306 |
static ProcessedMap *createProcessedMap(const Digraph &G) |
|
307 |
{ |
|
308 |
return new ProcessedMap(G); |
|
309 |
} |
|
310 |
}; |
|
311 |
///\brief \ref named-templ-param "Named parameter" |
|
312 |
///for setting the ProcessedMap type to be Digraph::NodeMap<bool>. |
|
313 |
/// |
|
314 |
///\ref named-templ-param "Named parameter" |
|
315 |
///for setting the ProcessedMap type to be Digraph::NodeMap<bool>. |
|
316 |
///If you don't set it explicitely, it will be automatically allocated. |
|
317 |
template <class T> |
|
318 |
class DefProcessedMapToBeDefaultMap : |
|
319 |
public Dfs< Digraph, DefDigraphProcessedMapTraits> { |
|
320 |
typedef Dfs< Digraph, DefDigraphProcessedMapTraits> Create; |
|
321 |
}; |
|
322 |
|
|
323 |
///@} |
|
324 |
|
|
325 |
public: |
|
326 |
|
|
327 |
///Constructor. |
|
328 |
|
|
329 |
///\param _G the digraph the algorithm will run on. |
|
330 |
/// |
|
331 |
Dfs(const Digraph& _G) : |
|
332 |
G(&_G), |
|
333 |
_pred(NULL), local_pred(false), |
|
334 |
_dist(NULL), local_dist(false), |
|
335 |
_reached(NULL), local_reached(false), |
|
336 |
_processed(NULL), local_processed(false) |
|
337 |
{ } |
|
338 |
|
|
339 |
///Destructor. |
|
340 |
~Dfs() |
|
341 |
{ |
|
342 |
if(local_pred) delete _pred; |
|
343 |
if(local_dist) delete _dist; |
|
344 |
if(local_reached) delete _reached; |
|
345 |
if(local_processed) delete _processed; |
|
346 |
} |
|
347 |
|
|
348 |
///Sets the map storing the predecessor arcs. |
|
349 |
|
|
350 |
///Sets the map storing the predecessor arcs. |
|
351 |
///If you don't use this function before calling \ref run(), |
|
352 |
///it will allocate one. The destuctor deallocates this |
|
353 |
///automatically allocated map, of course. |
|
354 |
///\return <tt> (*this) </tt> |
|
355 |
Dfs &predMap(PredMap &m) |
|
356 |
{ |
|
357 |
if(local_pred) { |
|
358 |
delete _pred; |
|
359 |
local_pred=false; |
|
360 |
} |
|
361 |
_pred = &m; |
|
362 |
return *this; |
|
363 |
} |
|
364 |
|
|
365 |
///Sets the map storing the distances calculated by the algorithm. |
|
366 |
|
|
367 |
///Sets the map storing the distances calculated by the algorithm. |
|
368 |
///If you don't use this function before calling \ref run(), |
|
369 |
///it will allocate one. The destuctor deallocates this |
|
370 |
///automatically allocated map, of course. |
|
371 |
///\return <tt> (*this) </tt> |
|
372 |
Dfs &distMap(DistMap &m) |
|
373 |
{ |
|
374 |
if(local_dist) { |
|
375 |
delete _dist; |
|
376 |
local_dist=false; |
|
377 |
} |
|
378 |
_dist = &m; |
|
379 |
return *this; |
|
380 |
} |
|
381 |
|
|
382 |
///Sets the map indicating if a node is reached. |
|
383 |
|
|
384 |
///Sets the map indicating if a node is reached. |
|
385 |
///If you don't use this function before calling \ref run(), |
|
386 |
///it will allocate one. The destuctor deallocates this |
|
387 |
///automatically allocated map, of course. |
|
388 |
///\return <tt> (*this) </tt> |
|
389 |
Dfs &reachedMap(ReachedMap &m) |
|
390 |
{ |
|
391 |
if(local_reached) { |
|
392 |
delete _reached; |
|
393 |
local_reached=false; |
|
394 |
} |
|
395 |
_reached = &m; |
|
396 |
return *this; |
|
397 |
} |
|
398 |
|
|
399 |
///Sets the map indicating if a node is processed. |
|
400 |
|
|
401 |
///Sets the map indicating if a node is processed. |
|
402 |
///If you don't use this function before calling \ref run(), |
|
403 |
///it will allocate one. The destuctor deallocates this |
|
404 |
///automatically allocated map, of course. |
|
405 |
///\return <tt> (*this) </tt> |
|
406 |
Dfs &processedMap(ProcessedMap &m) |
|
407 |
{ |
|
408 |
if(local_processed) { |
|
409 |
delete _processed; |
|
410 |
local_processed=false; |
|
411 |
} |
|
412 |
_processed = &m; |
|
413 |
return *this; |
|
414 |
} |
|
415 |
|
|
416 |
public: |
|
417 |
///\name Execution control |
|
418 |
///The simplest way to execute the algorithm is to use |
|
419 |
///one of the member functions called \c run(...). |
|
420 |
///\n |
|
421 |
///If you need more control on the execution, |
|
422 |
///first you must call \ref init(), then you can add a source node |
|
423 |
///with \ref addSource(). |
|
424 |
///Finally \ref start() will perform the actual path |
|
425 |
///computation. |
|
426 |
|
|
427 |
///@{ |
|
428 |
|
|
429 |
///Initializes the internal data structures. |
|
430 |
|
|
431 |
///Initializes the internal data structures. |
|
432 |
/// |
|
433 |
void init() |
|
434 |
{ |
|
435 |
create_maps(); |
|
436 |
_stack.resize(countNodes(*G)); |
|
437 |
_stack_head=-1; |
|
438 |
for ( NodeIt u(*G) ; u!=INVALID ; ++u ) { |
|
439 |
_pred->set(u,INVALID); |
|
440 |
// _predNode->set(u,INVALID); |
|
441 |
_reached->set(u,false); |
|
442 |
_processed->set(u,false); |
|
443 |
} |
|
444 |
} |
|
445 |
|
|
446 |
///Adds a new source node. |
|
447 |
|
|
448 |
///Adds a new source node to the set of nodes to be processed. |
|
449 |
/// |
|
450 |
///\warning dists are wrong (or at least strange) |
|
451 |
///in case of multiple sources. |
|
452 |
void addSource(Node s) |
|
453 |
{ |
|
454 |
if(!(*_reached)[s]) |
|
455 |
{ |
|
456 |
_reached->set(s,true); |
|
457 |
_pred->set(s,INVALID); |
|
458 |
OutArcIt e(*G,s); |
|
459 |
if(e!=INVALID) { |
|
460 |
_stack[++_stack_head]=e; |
|
461 |
_dist->set(s,_stack_head); |
|
462 |
} |
|
463 |
else { |
|
464 |
_processed->set(s,true); |
|
465 |
_dist->set(s,0); |
|
466 |
} |
|
467 |
} |
|
468 |
} |
|
469 |
|
|
470 |
///Processes the next arc. |
|
471 |
|
|
472 |
///Processes the next arc. |
|
473 |
/// |
|
474 |
///\return The processed arc. |
|
475 |
/// |
|
476 |
///\pre The stack must not be empty! |
|
477 |
Arc processNextArc() |
|
478 |
{ |
|
479 |
Node m; |
|
480 |
Arc e=_stack[_stack_head]; |
|
481 |
if(!(*_reached)[m=G->target(e)]) { |
|
482 |
_pred->set(m,e); |
|
483 |
_reached->set(m,true); |
|
484 |
++_stack_head; |
|
485 |
_stack[_stack_head] = OutArcIt(*G, m); |
|
486 |
_dist->set(m,_stack_head); |
|
487 |
} |
|
488 |
else { |
|
489 |
m=G->source(e); |
|
490 |
++_stack[_stack_head]; |
|
491 |
} |
|
492 |
while(_stack_head>=0 && _stack[_stack_head]==INVALID) { |
|
493 |
_processed->set(m,true); |
|
494 |
--_stack_head; |
|
495 |
if(_stack_head>=0) { |
|
496 |
m=G->source(_stack[_stack_head]); |
|
497 |
++_stack[_stack_head]; |
|
498 |
} |
|
499 |
} |
|
500 |
return e; |
|
501 |
} |
|
502 |
///Next arc to be processed. |
|
503 |
|
|
504 |
///Next arc to be processed. |
|
505 |
/// |
|
506 |
///\return The next arc to be processed or INVALID if the stack is |
|
507 |
/// empty. |
|
508 |
OutArcIt nextArc() |
|
509 |
{ |
|
510 |
return _stack_head>=0?_stack[_stack_head]:INVALID; |
|
511 |
} |
|
512 |
|
|
513 |
///\brief Returns \c false if there are nodes |
|
514 |
///to be processed in the queue |
|
515 |
/// |
|
516 |
///Returns \c false if there are nodes |
|
517 |
///to be processed in the queue |
|
518 |
bool emptyQueue() { return _stack_head<0; } |
|
519 |
///Returns the number of the nodes to be processed. |
|
520 |
|
|
521 |
///Returns the number of the nodes to be processed in the queue. |
|
522 |
int queueSize() { return _stack_head+1; } |
|
523 |
|
|
524 |
///Executes the algorithm. |
|
525 |
|
|
526 |
///Executes the algorithm. |
|
527 |
/// |
|
528 |
///\pre init() must be called and at least one node should be added |
|
529 |
///with addSource() before using this function. |
|
530 |
/// |
|
531 |
///This method runs the %DFS algorithm from the root node(s) |
|
532 |
///in order to |
|
533 |
///compute the |
|
534 |
///%DFS path to each node. The algorithm computes |
|
535 |
///- The %DFS tree. |
|
536 |
///- The distance of each node from the root(s) in the %DFS tree. |
|
537 |
/// |
|
538 |
void start() |
|
539 |
{ |
|
540 |
while ( !emptyQueue() ) processNextArc(); |
|
541 |
} |
|
542 |
|
|
543 |
///Executes the algorithm until \c dest is reached. |
|
544 |
|
|
545 |
///Executes the algorithm until \c dest is reached. |
|
546 |
/// |
|
547 |
///\pre init() must be called and at least one node should be added |
|
548 |
///with addSource() before using this function. |
|
549 |
/// |
|
550 |
///This method runs the %DFS algorithm from the root node(s) |
|
551 |
///in order to |
|
552 |
///compute the |
|
553 |
///%DFS path to \c dest. The algorithm computes |
|
554 |
///- The %DFS path to \c dest. |
|
555 |
///- The distance of \c dest from the root(s) in the %DFS tree. |
|
556 |
/// |
|
557 |
void start(Node dest) |
|
558 |
{ |
|
559 |
while ( !emptyQueue() && G->target(_stack[_stack_head])!=dest ) |
|
560 |
processNextArc(); |
|
561 |
} |
|
562 |
|
|
563 |
///Executes the algorithm until a condition is met. |
|
564 |
|
|
565 |
///Executes the algorithm until a condition is met. |
|
566 |
/// |
|
567 |
///\pre init() must be called and at least one node should be added |
|
568 |
///with addSource() before using this function. |
|
569 |
/// |
|
570 |
///\param em must be a bool (or convertible) arc map. The algorithm |
|
571 |
///will stop when it reaches an arc \c e with <tt>em[e]</tt> true. |
|
572 |
/// |
|
573 |
///\return The reached arc \c e with <tt>em[e]</tt> true or |
|
574 |
///\c INVALID if no such arc was found. |
|
575 |
/// |
|
576 |
///\warning Contrary to \ref Bfs and \ref Dijkstra, \c em is an arc map, |
|
577 |
///not a node map. |
|
578 |
template<class EM> |
|
579 |
Arc start(const EM &em) |
|
580 |
{ |
|
581 |
while ( !emptyQueue() && !em[_stack[_stack_head]] ) |
|
582 |
processNextArc(); |
|
583 |
return emptyQueue() ? INVALID : _stack[_stack_head]; |
|
584 |
} |
|
585 |
|
|
586 |
///Runs %DFS algorithm to visit all nodes in the digraph. |
|
587 |
|
|
588 |
///This method runs the %DFS algorithm in order to |
|
589 |
///compute the |
|
590 |
///%DFS path to each node. The algorithm computes |
|
591 |
///- The %DFS tree. |
|
592 |
///- The distance of each node from the root in the %DFS tree. |
|
593 |
/// |
|
594 |
///\note d.run() is just a shortcut of the following code. |
|
595 |
///\code |
|
596 |
/// d.init(); |
|
597 |
/// for (NodeIt it(digraph); it != INVALID; ++it) { |
|
598 |
/// if (!d.reached(it)) { |
|
599 |
/// d.addSource(it); |
|
600 |
/// d.start(); |
|
601 |
/// } |
|
602 |
/// } |
|
603 |
///\endcode |
|
604 |
void run() { |
|
605 |
init(); |
|
606 |
for (NodeIt it(*G); it != INVALID; ++it) { |
|
607 |
if (!reached(it)) { |
|
608 |
addSource(it); |
|
609 |
start(); |
|
610 |
} |
|
611 |
} |
|
612 |
} |
|
613 |
|
|
614 |
///Runs %DFS algorithm from node \c s. |
|
615 |
|
|
616 |
///This method runs the %DFS algorithm from a root node \c s |
|
617 |
///in order to |
|
618 |
///compute the |
|
619 |
///%DFS path to each node. The algorithm computes |
|
620 |
///- The %DFS tree. |
|
621 |
///- The distance of each node from the root in the %DFS tree. |
|
622 |
/// |
|
623 |
///\note d.run(s) is just a shortcut of the following code. |
|
624 |
///\code |
|
625 |
/// d.init(); |
|
626 |
/// d.addSource(s); |
|
627 |
/// d.start(); |
|
628 |
///\endcode |
|
629 |
void run(Node s) { |
|
630 |
init(); |
|
631 |
addSource(s); |
|
632 |
start(); |
|
633 |
} |
|
634 |
|
|
635 |
///Finds the %DFS path between \c s and \c t. |
|
636 |
|
|
637 |
///Finds the %DFS path between \c s and \c t. |
|
638 |
/// |
|
639 |
///\return The length of the %DFS s---t path if there exists one, |
|
640 |
///0 otherwise. |
|
641 |
///\note Apart from the return value, d.run(s,t) is |
|
642 |
///just a shortcut of the following code. |
|
643 |
///\code |
|
644 |
/// d.init(); |
|
645 |
/// d.addSource(s); |
|
646 |
/// d.start(t); |
|
647 |
///\endcode |
|
648 |
int run(Node s,Node t) { |
|
649 |
init(); |
|
650 |
addSource(s); |
|
651 |
start(t); |
|
652 |
return reached(t)?_stack_head+1:0; |
|
653 |
} |
|
654 |
|
|
655 |
///@} |
|
656 |
|
|
657 |
///\name Query Functions |
|
658 |
///The result of the %DFS algorithm can be obtained using these |
|
659 |
///functions.\n |
|
660 |
///Before the use of these functions, |
|
661 |
///either run() or start() must be called. |
|
662 |
|
|
663 |
///@{ |
|
664 |
|
|
665 |
typedef PredMapPath<Digraph, PredMap> Path; |
|
666 |
|
|
667 |
///Gives back the shortest path. |
|
668 |
|
|
669 |
///Gives back the shortest path. |
|
670 |
///\pre The \c t should be reachable from the source. |
|
671 |
Path path(Node t) |
|
672 |
{ |
|
673 |
return Path(*G, *_pred, t); |
|
674 |
} |
|
675 |
|
|
676 |
///The distance of a node from the root(s). |
|
677 |
|
|
678 |
///Returns the distance of a node from the root(s). |
|
679 |
///\pre \ref run() must be called before using this function. |
|
680 |
///\warning If node \c v is unreachable from the root(s) then the return |
|
681 |
///value of this funcion is undefined. |
|
682 |
int dist(Node v) const { return (*_dist)[v]; } |
|
683 |
|
|
684 |
///Returns the 'previous arc' of the %DFS tree. |
|
685 |
|
|
686 |
///For a node \c v it returns the 'previous arc' |
|
687 |
///of the %DFS path, |
|
688 |
///i.e. it returns the last arc of a %DFS path from the root(s) to \c |
|
689 |
///v. It is \ref INVALID |
|
690 |
///if \c v is unreachable from the root(s) or \c v is a root. The |
|
691 |
///%DFS tree used here is equal to the %DFS tree used in |
|
692 |
///\ref predNode(). |
|
693 |
///\pre Either \ref run() or \ref start() must be called before using |
|
694 |
///this function. |
|
695 |
Arc predArc(Node v) const { return (*_pred)[v];} |
|
696 |
|
|
697 |
///Returns the 'previous node' of the %DFS tree. |
|
698 |
|
|
699 |
///For a node \c v it returns the 'previous node' |
|
700 |
///of the %DFS tree, |
|
701 |
///i.e. it returns the last but one node from a %DFS path from the |
|
702 |
///root(s) to \c v. |
|
703 |
///It is INVALID if \c v is unreachable from the root(s) or |
|
704 |
///if \c v itself a root. |
|
705 |
///The %DFS tree used here is equal to the %DFS |
|
706 |
///tree used in \ref predArc(). |
|
707 |
///\pre Either \ref run() or \ref start() must be called before |
|
708 |
///using this function. |
|
709 |
Node predNode(Node v) const { return (*_pred)[v]==INVALID ? INVALID: |
|
710 |
G->source((*_pred)[v]); } |
|
711 |
|
|
712 |
///Returns a reference to the NodeMap of distances. |
|
713 |
|
|
714 |
///Returns a reference to the NodeMap of distances. |
|
715 |
///\pre Either \ref run() or \ref init() must |
|
716 |
///be called before using this function. |
|
717 |
const DistMap &distMap() const { return *_dist;} |
|
718 |
|
|
719 |
///Returns a reference to the %DFS arc-tree map. |
|
720 |
|
|
721 |
///Returns a reference to the NodeMap of the arcs of the |
|
722 |
///%DFS tree. |
|
723 |
///\pre Either \ref run() or \ref init() |
|
724 |
///must be called before using this function. |
|
725 |
const PredMap &predMap() const { return *_pred;} |
|
726 |
|
|
727 |
///Checks if a node is reachable from the root. |
|
728 |
|
|
729 |
///Returns \c true if \c v is reachable from the root(s). |
|
730 |
///\warning The source nodes are inditated as unreachable. |
|
731 |
///\pre Either \ref run() or \ref start() |
|
732 |
///must be called before using this function. |
|
733 |
/// |
|
734 |
bool reached(Node v) { return (*_reached)[v]; } |
|
735 |
|
|
736 |
///@} |
|
737 |
}; |
|
738 |
|
|
739 |
///Default traits class of Dfs function. |
|
740 |
|
|
741 |
///Default traits class of Dfs function. |
|
742 |
///\param GR Digraph type. |
|
743 |
template<class GR> |
|
744 |
struct DfsWizardDefaultTraits |
|
745 |
{ |
|
746 |
///The digraph type the algorithm runs on. |
|
747 |
typedef GR Digraph; |
|
748 |
///\brief The type of the map that stores the last |
|
749 |
///arcs of the %DFS paths. |
|
750 |
/// |
|
751 |
///The type of the map that stores the last |
|
752 |
///arcs of the %DFS paths. |
|
753 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
754 |
/// |
|
755 |
typedef NullMap<typename Digraph::Node,typename GR::Arc> PredMap; |
|
756 |
///Instantiates a PredMap. |
|
757 |
|
|
758 |
///This function instantiates a \ref PredMap. |
|
759 |
///\param g is the digraph, to which we would like to define the PredMap. |
|
760 |
///\todo The digraph alone may be insufficient to initialize |
|
761 |
#ifdef DOXYGEN |
|
762 |
static PredMap *createPredMap(const GR &g) |
|
763 |
#else |
|
764 |
static PredMap *createPredMap(const GR &) |
|
765 |
#endif |
|
766 |
{ |
|
767 |
return new PredMap(); |
|
768 |
} |
|
769 |
|
|
770 |
///The type of the map that indicates which nodes are processed. |
|
771 |
|
|
772 |
///The type of the map that indicates which nodes are processed. |
|
773 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
774 |
///\todo named parameter to set this type, function to read and write. |
|
775 |
typedef NullMap<typename Digraph::Node,bool> ProcessedMap; |
|
776 |
///Instantiates a ProcessedMap. |
|
777 |
|
|
778 |
///This function instantiates a \ref ProcessedMap. |
|
779 |
///\param g is the digraph, to which |
|
780 |
///we would like to define the \ref ProcessedMap |
|
781 |
#ifdef DOXYGEN |
|
782 |
static ProcessedMap *createProcessedMap(const GR &g) |
|
783 |
#else |
|
784 |
static ProcessedMap *createProcessedMap(const GR &) |
|
785 |
#endif |
|
786 |
{ |
|
787 |
return new ProcessedMap(); |
|
788 |
} |
|
789 |
///The type of the map that indicates which nodes are reached. |
|
790 |
|
|
791 |
///The type of the map that indicates which nodes are reached. |
|
792 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
793 |
///\todo named parameter to set this type, function to read and write. |
|
794 |
typedef typename Digraph::template NodeMap<bool> ReachedMap; |
|
795 |
///Instantiates a ReachedMap. |
|
796 |
|
|
797 |
///This function instantiates a \ref ReachedMap. |
|
798 |
///\param G is the digraph, to which |
|
799 |
///we would like to define the \ref ReachedMap. |
|
800 |
static ReachedMap *createReachedMap(const GR &G) |
|
801 |
{ |
|
802 |
return new ReachedMap(G); |
|
803 |
} |
|
804 |
///The type of the map that stores the dists of the nodes. |
|
805 |
|
|
806 |
///The type of the map that stores the dists of the nodes. |
|
807 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
808 |
/// |
|
809 |
typedef NullMap<typename Digraph::Node,int> DistMap; |
|
810 |
///Instantiates a DistMap. |
|
811 |
|
|
812 |
///This function instantiates a \ref DistMap. |
|
813 |
///\param g is the digraph, to which we would like to define the \ref DistMap |
|
814 |
#ifdef DOXYGEN |
|
815 |
static DistMap *createDistMap(const GR &g) |
|
816 |
#else |
|
817 |
static DistMap *createDistMap(const GR &) |
|
818 |
#endif |
|
819 |
{ |
|
820 |
return new DistMap(); |
|
821 |
} |
|
822 |
}; |
|
823 |
|
|
824 |
/// Default traits used by \ref DfsWizard |
|
825 |
|
|
826 |
/// To make it easier to use Dfs algorithm |
|
827 |
///we have created a wizard class. |
|
828 |
/// This \ref DfsWizard class needs default traits, |
|
829 |
///as well as the \ref Dfs class. |
|
830 |
/// The \ref DfsWizardBase is a class to be the default traits of the |
|
831 |
/// \ref DfsWizard class. |
|
832 |
template<class GR> |
|
833 |
class DfsWizardBase : public DfsWizardDefaultTraits<GR> |
|
834 |
{ |
|
835 |
|
|
836 |
typedef DfsWizardDefaultTraits<GR> Base; |
|
837 |
protected: |
|
838 |
/// Type of the nodes in the digraph. |
|
839 |
typedef typename Base::Digraph::Node Node; |
|
840 |
|
|
841 |
/// Pointer to the underlying digraph. |
|
842 |
void *_g; |
|
843 |
///Pointer to the map of reached nodes. |
|
844 |
void *_reached; |
|
845 |
///Pointer to the map of processed nodes. |
|
846 |
void *_processed; |
|
847 |
///Pointer to the map of predecessors arcs. |
|
848 |
void *_pred; |
|
849 |
///Pointer to the map of distances. |
|
850 |
void *_dist; |
|
851 |
///Pointer to the source node. |
|
852 |
Node _source; |
|
853 |
|
|
854 |
public: |
|
855 |
/// Constructor. |
|
856 |
|
|
857 |
/// This constructor does not require parameters, therefore it initiates |
|
858 |
/// all of the attributes to default values (0, INVALID). |
|
859 |
DfsWizardBase() : _g(0), _reached(0), _processed(0), _pred(0), |
|
860 |
_dist(0), _source(INVALID) {} |
|
861 |
|
|
862 |
/// Constructor. |
|
863 |
|
|
864 |
/// This constructor requires some parameters, |
|
865 |
/// listed in the parameters list. |
|
866 |
/// Others are initiated to 0. |
|
867 |
/// \param g is the initial value of \ref _g |
|
868 |
/// \param s is the initial value of \ref _source |
|
869 |
DfsWizardBase(const GR &g, Node s=INVALID) : |
|
870 |
_g(reinterpret_cast<void*>(const_cast<GR*>(&g))), |
|
871 |
_reached(0), _processed(0), _pred(0), _dist(0), _source(s) {} |
|
872 |
|
|
873 |
}; |
|
874 |
|
|
875 |
/// A class to make the usage of the Dfs algorithm easier |
|
876 |
|
|
877 |
/// This class is created to make it easier to use the Dfs algorithm. |
|
878 |
/// It uses the functions and features of the plain \ref Dfs, |
|
879 |
/// but it is much simpler to use it. |
|
880 |
/// |
|
881 |
/// Simplicity means that the way to change the types defined |
|
882 |
/// in the traits class is based on functions that returns the new class |
|
883 |
/// and not on templatable built-in classes. |
|
884 |
/// When using the plain \ref Dfs |
|
885 |
/// the new class with the modified type comes from |
|
886 |
/// the original class by using the :: |
|
887 |
/// operator. In the case of \ref DfsWizard only |
|
888 |
/// a function have to be called and it will |
|
889 |
/// return the needed class. |
|
890 |
/// |
|
891 |
/// It does not have own \ref run method. When its \ref run method is called |
|
892 |
/// it initiates a plain \ref Dfs object, and calls the \ref Dfs::run |
|
893 |
/// method of it. |
|
894 |
template<class TR> |
|
895 |
class DfsWizard : public TR |
|
896 |
{ |
|
897 |
typedef TR Base; |
|
898 |
|
|
899 |
///The type of the underlying digraph. |
|
900 |
typedef typename TR::Digraph Digraph; |
|
901 |
//\e |
|
902 |
typedef typename Digraph::Node Node; |
|
903 |
//\e |
|
904 |
typedef typename Digraph::NodeIt NodeIt; |
|
905 |
//\e |
|
906 |
typedef typename Digraph::Arc Arc; |
|
907 |
//\e |
|
908 |
typedef typename Digraph::OutArcIt OutArcIt; |
|
909 |
|
|
910 |
///\brief The type of the map that stores |
|
911 |
///the reached nodes |
|
912 |
typedef typename TR::ReachedMap ReachedMap; |
|
913 |
///\brief The type of the map that stores |
|
914 |
///the processed nodes |
|
915 |
typedef typename TR::ProcessedMap ProcessedMap; |
|
916 |
///\brief The type of the map that stores the last |
|
917 |
///arcs of the %DFS paths. |
|
918 |
typedef typename TR::PredMap PredMap; |
|
919 |
///The type of the map that stores the distances of the nodes. |
|
920 |
typedef typename TR::DistMap DistMap; |
|
921 |
|
|
922 |
public: |
|
923 |
/// Constructor. |
|
924 |
DfsWizard() : TR() {} |
|
925 |
|
|
926 |
/// Constructor that requires parameters. |
|
927 |
|
|
928 |
/// Constructor that requires parameters. |
|
929 |
/// These parameters will be the default values for the traits class. |
|
930 |
DfsWizard(const Digraph &g, Node s=INVALID) : |
|
931 |
TR(g,s) {} |
|
932 |
|
|
933 |
///Copy constructor |
|
934 |
DfsWizard(const TR &b) : TR(b) {} |
|
935 |
|
|
936 |
~DfsWizard() {} |
|
937 |
|
|
938 |
///Runs Dfs algorithm from a given node. |
|
939 |
|
|
940 |
///Runs Dfs algorithm from a given node. |
|
941 |
///The node can be given by the \ref source function. |
|
942 |
void run() |
|
943 |
{ |
|
944 |
if(Base::_source==INVALID) throw UninitializedParameter(); |
|
945 |
Dfs<Digraph,TR> alg(*reinterpret_cast<const Digraph*>(Base::_g)); |
|
946 |
if(Base::_reached) |
|
947 |
alg.reachedMap(*reinterpret_cast<ReachedMap*>(Base::_reached)); |
|
948 |
if(Base::_processed) |
|
949 |
alg.processedMap(*reinterpret_cast<ProcessedMap*>(Base::_processed)); |
|
950 |
if(Base::_pred) |
|
951 |
alg.predMap(*reinterpret_cast<PredMap*>(Base::_pred)); |
|
952 |
if(Base::_dist) |
|
953 |
alg.distMap(*reinterpret_cast<DistMap*>(Base::_dist)); |
|
954 |
alg.run(Base::_source); |
|
955 |
} |
|
956 |
|
|
957 |
///Runs Dfs algorithm from the given node. |
|
958 |
|
|
959 |
///Runs Dfs algorithm from the given node. |
|
960 |
///\param s is the given source. |
|
961 |
void run(Node s) |
|
962 |
{ |
|
963 |
Base::_source=s; |
|
964 |
run(); |
|
965 |
} |
|
966 |
|
|
967 |
template<class T> |
|
968 |
struct DefPredMapBase : public Base { |
|
969 |
typedef T PredMap; |
|
970 |
static PredMap *createPredMap(const Digraph &) { return 0; }; |
|
971 |
DefPredMapBase(const TR &b) : TR(b) {} |
|
972 |
}; |
|
973 |
|
|
974 |
///\brief \ref named-templ-param "Named parameter" |
|
975 |
///function for setting PredMap type |
|
976 |
/// |
|
977 |
/// \ref named-templ-param "Named parameter" |
|
978 |
///function for setting PredMap type |
|
979 |
/// |
|
980 |
template<class T> |
|
981 |
DfsWizard<DefPredMapBase<T> > predMap(const T &t) |
|
982 |
{ |
|
983 |
Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t)); |
|
984 |
return DfsWizard<DefPredMapBase<T> >(*this); |
|
985 |
} |
|
986 |
|
|
987 |
|
|
988 |
template<class T> |
|
989 |
struct DefReachedMapBase : public Base { |
|
990 |
typedef T ReachedMap; |
|
991 |
static ReachedMap *createReachedMap(const Digraph &) { return 0; }; |
|
992 |
DefReachedMapBase(const TR &b) : TR(b) {} |
|
993 |
}; |
|
994 |
|
|
995 |
///\brief \ref named-templ-param "Named parameter" |
|
996 |
///function for setting ReachedMap |
|
997 |
/// |
|
998 |
/// \ref named-templ-param "Named parameter" |
|
999 |
///function for setting ReachedMap |
|
1000 |
/// |
|
1001 |
template<class T> |
|
1002 |
DfsWizard<DefReachedMapBase<T> > reachedMap(const T &t) |
|
1003 |
{ |
|
1004 |
Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t)); |
|
1005 |
return DfsWizard<DefReachedMapBase<T> >(*this); |
|
1006 |
} |
|
1007 |
|
|
1008 |
|
|
1009 |
template<class T> |
|
1010 |
struct DefProcessedMapBase : public Base { |
|
1011 |
typedef T ProcessedMap; |
|
1012 |
static ProcessedMap *createProcessedMap(const Digraph &) { return 0; }; |
|
1013 |
DefProcessedMapBase(const TR &b) : TR(b) {} |
|
1014 |
}; |
|
1015 |
|
|
1016 |
///\brief \ref named-templ-param "Named parameter" |
|
1017 |
///function for setting ProcessedMap |
|
1018 |
/// |
|
1019 |
/// \ref named-templ-param "Named parameter" |
|
1020 |
///function for setting ProcessedMap |
|
1021 |
/// |
|
1022 |
template<class T> |
|
1023 |
DfsWizard<DefProcessedMapBase<T> > processedMap(const T &t) |
|
1024 |
{ |
|
1025 |
Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t)); |
|
1026 |
return DfsWizard<DefProcessedMapBase<T> >(*this); |
|
1027 |
} |
|
1028 |
|
|
1029 |
template<class T> |
|
1030 |
struct DefDistMapBase : public Base { |
|
1031 |
typedef T DistMap; |
|
1032 |
static DistMap *createDistMap(const Digraph &) { return 0; }; |
|
1033 |
DefDistMapBase(const TR &b) : TR(b) {} |
|
1034 |
}; |
|
1035 |
|
|
1036 |
///\brief \ref named-templ-param "Named parameter" |
|
1037 |
///function for setting DistMap type |
|
1038 |
/// |
|
1039 |
/// \ref named-templ-param "Named parameter" |
|
1040 |
///function for setting DistMap type |
|
1041 |
/// |
|
1042 |
template<class T> |
|
1043 |
DfsWizard<DefDistMapBase<T> > distMap(const T &t) |
|
1044 |
{ |
|
1045 |
Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t)); |
|
1046 |
return DfsWizard<DefDistMapBase<T> >(*this); |
|
1047 |
} |
|
1048 |
|
|
1049 |
/// Sets the source node, from which the Dfs algorithm runs. |
|
1050 |
|
|
1051 |
/// Sets the source node, from which the Dfs algorithm runs. |
|
1052 |
/// \param s is the source node. |
|
1053 |
DfsWizard<TR> &source(Node s) |
|
1054 |
{ |
|
1055 |
Base::_source=s; |
|
1056 |
return *this; |
|
1057 |
} |
|
1058 |
|
|
1059 |
}; |
|
1060 |
|
|
1061 |
///Function type interface for Dfs algorithm. |
|
1062 |
|
|
1063 |
///\ingroup search |
|
1064 |
///Function type interface for Dfs algorithm. |
|
1065 |
/// |
|
1066 |
///This function also has several |
|
1067 |
///\ref named-templ-func-param "named parameters", |
|
1068 |
///they are declared as the members of class \ref DfsWizard. |
|
1069 |
///The following |
|
1070 |
///example shows how to use these parameters. |
|
1071 |
///\code |
|
1072 |
/// dfs(g,source).predMap(preds).run(); |
|
1073 |
///\endcode |
|
1074 |
///\warning Don't forget to put the \ref DfsWizard::run() "run()" |
|
1075 |
///to the end of the parameter list. |
|
1076 |
///\sa DfsWizard |
|
1077 |
///\sa Dfs |
|
1078 |
template<class GR> |
|
1079 |
DfsWizard<DfsWizardBase<GR> > |
|
1080 |
dfs(const GR &g,typename GR::Node s=INVALID) |
|
1081 |
{ |
|
1082 |
return DfsWizard<DfsWizardBase<GR> >(g,s); |
|
1083 |
} |
|
1084 |
|
|
1085 |
#ifdef DOXYGEN |
|
1086 |
/// \brief Visitor class for dfs. |
|
1087 |
/// |
|
1088 |
/// It gives a simple interface for a functional interface for dfs |
|
1089 |
/// traversal. The traversal on a linear data structure. |
|
1090 |
template <typename _Digraph> |
|
1091 |
struct DfsVisitor { |
|
1092 |
typedef _Digraph Digraph; |
|
1093 |
typedef typename Digraph::Arc Arc; |
|
1094 |
typedef typename Digraph::Node Node; |
|
1095 |
/// \brief Called when the arc reach a node. |
|
1096 |
/// |
|
1097 |
/// It is called when the dfs find an arc which target is not |
|
1098 |
/// reached yet. |
|
1099 |
void discover(const Arc& arc) {} |
|
1100 |
/// \brief Called when the node reached first time. |
|
1101 |
/// |
|
1102 |
/// It is Called when the node reached first time. |
|
1103 |
void reach(const Node& node) {} |
|
1104 |
/// \brief Called when we step back on an arc. |
|
1105 |
/// |
|
1106 |
/// It is called when the dfs should step back on the arc. |
|
1107 |
void backtrack(const Arc& arc) {} |
|
1108 |
/// \brief Called when we step back from the node. |
|
1109 |
/// |
|
1110 |
/// It is called when we step back from the node. |
|
1111 |
void leave(const Node& node) {} |
|
1112 |
/// \brief Called when the arc examined but target of the arc |
|
1113 |
/// already discovered. |
|
1114 |
/// |
|
1115 |
/// It called when the arc examined but the target of the arc |
|
1116 |
/// already discovered. |
|
1117 |
void examine(const Arc& arc) {} |
|
1118 |
/// \brief Called for the source node of the dfs. |
|
1119 |
/// |
|
1120 |
/// It is called for the source node of the dfs. |
|
1121 |
void start(const Node& node) {} |
|
1122 |
/// \brief Called when we leave the source node of the dfs. |
|
1123 |
/// |
|
1124 |
/// It is called when we leave the source node of the dfs. |
|
1125 |
void stop(const Node& node) {} |
|
1126 |
|
|
1127 |
}; |
|
1128 |
#else |
|
1129 |
template <typename _Digraph> |
|
1130 |
struct DfsVisitor { |
|
1131 |
typedef _Digraph Digraph; |
|
1132 |
typedef typename Digraph::Arc Arc; |
|
1133 |
typedef typename Digraph::Node Node; |
|
1134 |
void discover(const Arc&) {} |
|
1135 |
void reach(const Node&) {} |
|
1136 |
void backtrack(const Arc&) {} |
|
1137 |
void leave(const Node&) {} |
|
1138 |
void examine(const Arc&) {} |
|
1139 |
void start(const Node&) {} |
|
1140 |
void stop(const Node&) {} |
|
1141 |
|
|
1142 |
template <typename _Visitor> |
|
1143 |
struct Constraints { |
|
1144 |
void constraints() { |
|
1145 |
Arc arc; |
|
1146 |
Node node; |
|
1147 |
visitor.discover(arc); |
|
1148 |
visitor.reach(node); |
|
1149 |
visitor.backtrack(arc); |
|
1150 |
visitor.leave(node); |
|
1151 |
visitor.examine(arc); |
|
1152 |
visitor.start(node); |
|
1153 |
visitor.stop(arc); |
|
1154 |
} |
|
1155 |
_Visitor& visitor; |
|
1156 |
}; |
|
1157 |
}; |
|
1158 |
#endif |
|
1159 |
|
|
1160 |
/// \brief Default traits class of DfsVisit class. |
|
1161 |
/// |
|
1162 |
/// Default traits class of DfsVisit class. |
|
1163 |
/// \param _Digraph Digraph type. |
|
1164 |
template<class _Digraph> |
|
1165 |
struct DfsVisitDefaultTraits { |
|
1166 |
|
|
1167 |
/// \brief The digraph type the algorithm runs on. |
|
1168 |
typedef _Digraph Digraph; |
|
1169 |
|
|
1170 |
/// \brief The type of the map that indicates which nodes are reached. |
|
1171 |
/// |
|
1172 |
/// The type of the map that indicates which nodes are reached. |
|
1173 |
/// It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
1174 |
/// \todo named parameter to set this type, function to read and write. |
|
1175 |
typedef typename Digraph::template NodeMap<bool> ReachedMap; |
|
1176 |
|
|
1177 |
/// \brief Instantiates a ReachedMap. |
|
1178 |
/// |
|
1179 |
/// This function instantiates a \ref ReachedMap. |
|
1180 |
/// \param digraph is the digraph, to which |
|
1181 |
/// we would like to define the \ref ReachedMap. |
|
1182 |
static ReachedMap *createReachedMap(const Digraph &digraph) { |
|
1183 |
return new ReachedMap(digraph); |
|
1184 |
} |
|
1185 |
|
|
1186 |
}; |
|
1187 |
|
|
1188 |
/// %DFS Visit algorithm class. |
|
1189 |
|
|
1190 |
/// \ingroup search |
|
1191 |
/// This class provides an efficient implementation of the %DFS algorithm |
|
1192 |
/// with visitor interface. |
|
1193 |
/// |
|
1194 |
/// The %DfsVisit class provides an alternative interface to the Dfs |
|
1195 |
/// class. It works with callback mechanism, the DfsVisit object calls |
|
1196 |
/// on every dfs event the \c Visitor class member functions. |
|
1197 |
/// |
|
1198 |
/// \param _Digraph The digraph type the algorithm runs on. The default value is |
|
1199 |
/// \ref ListDigraph. The value of _Digraph is not used directly by Dfs, it |
|
1200 |
/// is only passed to \ref DfsDefaultTraits. |
|
1201 |
/// \param _Visitor The Visitor object for the algorithm. The |
|
1202 |
/// \ref DfsVisitor "DfsVisitor<_Digraph>" is an empty Visitor which |
|
1203 |
/// does not observe the Dfs events. If you want to observe the dfs |
|
1204 |
/// events you should implement your own Visitor class. |
|
1205 |
/// \param _Traits Traits class to set various data types used by the |
|
1206 |
/// algorithm. The default traits class is |
|
1207 |
/// \ref DfsVisitDefaultTraits "DfsVisitDefaultTraits<_Digraph>". |
|
1208 |
/// See \ref DfsVisitDefaultTraits for the documentation of |
|
1209 |
/// a Dfs visit traits class. |
|
1210 |
/// |
|
1211 |
/// \author Jacint Szabo, Alpar Juttner and Balazs Dezso |
|
1212 |
#ifdef DOXYGEN |
|
1213 |
template <typename _Digraph, typename _Visitor, typename _Traits> |
|
1214 |
#else |
|
1215 |
template <typename _Digraph = ListDigraph, |
|
1216 |
typename _Visitor = DfsVisitor<_Digraph>, |
|
1217 |
typename _Traits = DfsDefaultTraits<_Digraph> > |
|
1218 |
#endif |
|
1219 |
class DfsVisit { |
|
1220 |
public: |
|
1221 |
|
|
1222 |
/// \brief \ref Exception for uninitialized parameters. |
|
1223 |
/// |
|
1224 |
/// This error represents problems in the initialization |
|
1225 |
/// of the parameters of the algorithms. |
|
1226 |
class UninitializedParameter : public lemon::UninitializedParameter { |
|
1227 |
public: |
|
1228 |
virtual const char* what() const throw() |
|
1229 |
{ |
|
1230 |
return "lemon::DfsVisit::UninitializedParameter"; |
|
1231 |
} |
|
1232 |
}; |
|
1233 |
|
|
1234 |
typedef _Traits Traits; |
|
1235 |
|
|
1236 |
typedef typename Traits::Digraph Digraph; |
|
1237 |
|
|
1238 |
typedef _Visitor Visitor; |
|
1239 |
|
|
1240 |
///The type of the map indicating which nodes are reached. |
|
1241 |
typedef typename Traits::ReachedMap ReachedMap; |
|
1242 |
|
|
1243 |
private: |
|
1244 |
|
|
1245 |
typedef typename Digraph::Node Node; |
|
1246 |
typedef typename Digraph::NodeIt NodeIt; |
|
1247 |
typedef typename Digraph::Arc Arc; |
|
1248 |
typedef typename Digraph::OutArcIt OutArcIt; |
|
1249 |
|
|
1250 |
/// Pointer to the underlying digraph. |
|
1251 |
const Digraph *_digraph; |
|
1252 |
/// Pointer to the visitor object. |
|
1253 |
Visitor *_visitor; |
|
1254 |
///Pointer to the map of reached status of the nodes. |
|
1255 |
ReachedMap *_reached; |
|
1256 |
///Indicates if \ref _reached is locally allocated (\c true) or not. |
|
1257 |
bool local_reached; |
|
1258 |
|
|
1259 |
std::vector<typename Digraph::Arc> _stack; |
|
1260 |
int _stack_head; |
|
1261 |
|
|
1262 |
/// \brief Creates the maps if necessary. |
|
1263 |
/// |
|
1264 |
/// Creates the maps if necessary. |
|
1265 |
void create_maps() { |
|
1266 |
if(!_reached) { |
|
1267 |
local_reached = true; |
|
1268 |
_reached = Traits::createReachedMap(*_digraph); |
|
1269 |
} |
|
1270 |
} |
|
1271 |
|
|
1272 |
protected: |
|
1273 |
|
|
1274 |
DfsVisit() {} |
|
1275 |
|
|
1276 |
public: |
|
1277 |
|
|
1278 |
typedef DfsVisit Create; |
|
1279 |
|
|
1280 |
/// \name Named template parameters |
|
1281 |
|
|
1282 |
///@{ |
|
1283 |
template <class T> |
|
1284 |
struct DefReachedMapTraits : public Traits { |
|
1285 |
typedef T ReachedMap; |
|
1286 |
static ReachedMap *createReachedMap(const Digraph &digraph) { |
|
1287 |
throw UninitializedParameter(); |
|
1288 |
} |
|
1289 |
}; |
|
1290 |
/// \brief \ref named-templ-param "Named parameter" for setting |
|
1291 |
/// ReachedMap type |
|
1292 |
/// |
|
1293 |
/// \ref named-templ-param "Named parameter" for setting ReachedMap type |
|
1294 |
template <class T> |
|
1295 |
struct DefReachedMap : public DfsVisit< Digraph, Visitor, |
|
1296 |
DefReachedMapTraits<T> > { |
|
1297 |
typedef DfsVisit< Digraph, Visitor, DefReachedMapTraits<T> > Create; |
|
1298 |
}; |
|
1299 |
///@} |
|
1300 |
|
|
1301 |
public: |
|
1302 |
|
|
1303 |
/// \brief Constructor. |
|
1304 |
/// |
|
1305 |
/// Constructor. |
|
1306 |
/// |
|
1307 |
/// \param digraph the digraph the algorithm will run on. |
|
1308 |
/// \param visitor The visitor of the algorithm. |
|
1309 |
/// |
|
1310 |
DfsVisit(const Digraph& digraph, Visitor& visitor) |
|
1311 |
: _digraph(&digraph), _visitor(&visitor), |
|
1312 |
_reached(0), local_reached(false) {} |
|
1313 |
|
|
1314 |
/// \brief Destructor. |
|
1315 |
/// |
|
1316 |
/// Destructor. |
|
1317 |
~DfsVisit() { |
|
1318 |
if(local_reached) delete _reached; |
|
1319 |
} |
|
1320 |
|
|
1321 |
/// \brief Sets the map indicating if a node is reached. |
|
1322 |
/// |
|
1323 |
/// Sets the map indicating if a node is reached. |
|
1324 |
/// If you don't use this function before calling \ref run(), |
|
1325 |
/// it will allocate one. The destuctor deallocates this |
|
1326 |
/// automatically allocated map, of course. |
|
1327 |
/// \return <tt> (*this) </tt> |
|
1328 |
DfsVisit &reachedMap(ReachedMap &m) { |
|
1329 |
if(local_reached) { |
|
1330 |
delete _reached; |
|
1331 |
local_reached=false; |
|
1332 |
} |
|
1333 |
_reached = &m; |
|
1334 |
return *this; |
|
1335 |
} |
|
1336 |
|
|
1337 |
public: |
|
1338 |
/// \name Execution control |
|
1339 |
/// The simplest way to execute the algorithm is to use |
|
1340 |
/// one of the member functions called \c run(...). |
|
1341 |
/// \n |
|
1342 |
/// If you need more control on the execution, |
|
1343 |
/// first you must call \ref init(), then you can adda source node |
|
1344 |
/// with \ref addSource(). |
|
1345 |
/// Finally \ref start() will perform the actual path |
|
1346 |
/// computation. |
|
1347 |
|
|
1348 |
/// @{ |
|
1349 |
/// \brief Initializes the internal data structures. |
|
1350 |
/// |
|
1351 |
/// Initializes the internal data structures. |
|
1352 |
/// |
|
1353 |
void init() { |
|
1354 |
create_maps(); |
|
1355 |
_stack.resize(countNodes(*_digraph)); |
|
1356 |
_stack_head = -1; |
|
1357 |
for (NodeIt u(*_digraph) ; u != INVALID ; ++u) { |
|
1358 |
_reached->set(u, false); |
|
1359 |
} |
|
1360 |
} |
|
1361 |
|
|
1362 |
/// \brief Adds a new source node. |
|
1363 |
/// |
|
1364 |
/// Adds a new source node to the set of nodes to be processed. |
|
1365 |
void addSource(Node s) { |
|
1366 |
if(!(*_reached)[s]) { |
|
1367 |
_reached->set(s,true); |
|
1368 |
_visitor->start(s); |
|
1369 |
_visitor->reach(s); |
|
1370 |
Arc e; |
|
1371 |
_digraph->firstOut(e, s); |
|
1372 |
if (e != INVALID) { |
|
1373 |
_stack[++_stack_head] = e; |
|
1374 |
} else { |
|
1375 |
_visitor->leave(s); |
|
1376 |
} |
|
1377 |
} |
|
1378 |
} |
|
1379 |
|
|
1380 |
/// \brief Processes the next arc. |
|
1381 |
/// |
|
1382 |
/// Processes the next arc. |
|
1383 |
/// |
|
1384 |
/// \return The processed arc. |
|
1385 |
/// |
|
1386 |
/// \pre The stack must not be empty! |
|
1387 |
Arc processNextArc() { |
|
1388 |
Arc e = _stack[_stack_head]; |
|
1389 |
Node m = _digraph->target(e); |
|
1390 |
if(!(*_reached)[m]) { |
|
1391 |
_visitor->discover(e); |
|
1392 |
_visitor->reach(m); |
|
1393 |
_reached->set(m, true); |
|
1394 |
_digraph->firstOut(_stack[++_stack_head], m); |
|
1395 |
} else { |
|
1396 |
_visitor->examine(e); |
|
1397 |
m = _digraph->source(e); |
|
1398 |
_digraph->nextOut(_stack[_stack_head]); |
|
1399 |
} |
|
1400 |
while (_stack_head>=0 && _stack[_stack_head] == INVALID) { |
|
1401 |
_visitor->leave(m); |
|
1402 |
--_stack_head; |
|
1403 |
if (_stack_head >= 0) { |
|
1404 |
_visitor->backtrack(_stack[_stack_head]); |
|
1405 |
m = _digraph->source(_stack[_stack_head]); |
|
1406 |
_digraph->nextOut(_stack[_stack_head]); |
|
1407 |
} else { |
|
1408 |
_visitor->stop(m); |
|
1409 |
} |
|
1410 |
} |
|
1411 |
return e; |
|
1412 |
} |
|
1413 |
|
|
1414 |
/// \brief Next arc to be processed. |
|
1415 |
/// |
|
1416 |
/// Next arc to be processed. |
|
1417 |
/// |
|
1418 |
/// \return The next arc to be processed or INVALID if the stack is |
|
1419 |
/// empty. |
|
1420 |
Arc nextArc() { |
|
1421 |
return _stack_head >= 0 ? _stack[_stack_head] : INVALID; |
|
1422 |
} |
|
1423 |
|
|
1424 |
/// \brief Returns \c false if there are nodes |
|
1425 |
/// to be processed in the queue |
|
1426 |
/// |
|
1427 |
/// Returns \c false if there are nodes |
|
1428 |
/// to be processed in the queue |
|
1429 |
bool emptyQueue() { return _stack_head < 0; } |
|
1430 |
|
|
1431 |
/// \brief Returns the number of the nodes to be processed. |
|
1432 |
/// |
|
1433 |
/// Returns the number of the nodes to be processed in the queue. |
|
1434 |
int queueSize() { return _stack_head + 1; } |
|
1435 |
|
|
1436 |
/// \brief Executes the algorithm. |
|
1437 |
/// |
|
1438 |
/// Executes the algorithm. |
|
1439 |
/// |
|
1440 |
/// \pre init() must be called and at least one node should be added |
|
1441 |
/// with addSource() before using this function. |
|
1442 |
void start() { |
|
1443 |
while ( !emptyQueue() ) processNextArc(); |
|
1444 |
} |
|
1445 |
|
|
1446 |
/// \brief Executes the algorithm until \c dest is reached. |
|
1447 |
/// |
|
1448 |
/// Executes the algorithm until \c dest is reached. |
|
1449 |
/// |
|
1450 |
/// \pre init() must be called and at least one node should be added |
|
1451 |
/// with addSource() before using this function. |
|
1452 |
void start(Node dest) { |
|
1453 |
while ( !emptyQueue() && _digraph->target(_stack[_stack_head]) != dest ) |
|
1454 |
processNextArc(); |
|
1455 |
} |
|
1456 |
|
|
1457 |
/// \brief Executes the algorithm until a condition is met. |
|
1458 |
/// |
|
1459 |
/// Executes the algorithm until a condition is met. |
|
1460 |
/// |
|
1461 |
/// \pre init() must be called and at least one node should be added |
|
1462 |
/// with addSource() before using this function. |
|
1463 |
/// |
|
1464 |
/// \param em must be a bool (or convertible) arc map. The algorithm |
|
1465 |
/// will stop when it reaches an arc \c e with <tt>em[e]</tt> true. |
|
1466 |
/// |
|
1467 |
///\return The reached arc \c e with <tt>em[e]</tt> true or |
|
1468 |
///\c INVALID if no such arc was found. |
|
1469 |
/// |
|
1470 |
/// \warning Contrary to \ref Bfs and \ref Dijkstra, \c em is an arc map, |
|
1471 |
/// not a node map. |
|
1472 |
template <typename EM> |
|
1473 |
Arc start(const EM &em) { |
|
1474 |
while ( !emptyQueue() && !em[_stack[_stack_head]] ) |
|
1475 |
processNextArc(); |
|
1476 |
return emptyQueue() ? INVALID : _stack[_stack_head]; |
|
1477 |
} |
|
1478 |
|
|
1479 |
/// \brief Runs %DFSVisit algorithm from node \c s. |
|
1480 |
/// |
|
1481 |
/// This method runs the %DFS algorithm from a root node \c s. |
|
1482 |
/// \note d.run(s) is just a shortcut of the following code. |
|
1483 |
///\code |
|
1484 |
/// d.init(); |
|
1485 |
/// d.addSource(s); |
|
1486 |
/// d.start(); |
|
1487 |
///\endcode |
|
1488 |
void run(Node s) { |
|
1489 |
init(); |
|
1490 |
addSource(s); |
|
1491 |
start(); |
|
1492 |
} |
|
1493 |
|
|
1494 |
/// \brief Runs %DFSVisit algorithm to visit all nodes in the digraph. |
|
1495 |
|
|
1496 |
/// This method runs the %DFS algorithm in order to |
|
1497 |
/// compute the %DFS path to each node. The algorithm computes |
|
1498 |
/// - The %DFS tree. |
|
1499 |
/// - The distance of each node from the root in the %DFS tree. |
|
1500 |
/// |
|
1501 |
///\note d.run() is just a shortcut of the following code. |
|
1502 |
///\code |
|
1503 |
/// d.init(); |
|
1504 |
/// for (NodeIt it(digraph); it != INVALID; ++it) { |
|
1505 |
/// if (!d.reached(it)) { |
|
1506 |
/// d.addSource(it); |
|
1507 |
/// d.start(); |
|
1508 |
/// } |
|
1509 |
/// } |
|
1510 |
///\endcode |
|
1511 |
void run() { |
|
1512 |
init(); |
|
1513 |
for (NodeIt it(*_digraph); it != INVALID; ++it) { |
|
1514 |
if (!reached(it)) { |
|
1515 |
addSource(it); |
|
1516 |
start(); |
|
1517 |
} |
|
1518 |
} |
|
1519 |
} |
|
1520 |
///@} |
|
1521 |
|
|
1522 |
/// \name Query Functions |
|
1523 |
/// The result of the %DFS algorithm can be obtained using these |
|
1524 |
/// functions.\n |
|
1525 |
/// Before the use of these functions, |
|
1526 |
/// either run() or start() must be called. |
|
1527 |
///@{ |
|
1528 |
/// \brief Checks if a node is reachable from the root. |
|
1529 |
/// |
|
1530 |
/// Returns \c true if \c v is reachable from the root(s). |
|
1531 |
/// \warning The source nodes are inditated as unreachable. |
|
1532 |
/// \pre Either \ref run() or \ref start() |
|
1533 |
/// must be called before using this function. |
|
1534 |
/// |
|
1535 |
bool reached(Node v) { return (*_reached)[v]; } |
|
1536 |
///@} |
|
1537 |
}; |
|
1538 |
|
|
1539 |
|
|
1540 |
} //END OF NAMESPACE LEMON |
|
1541 |
|
|
1542 |
#endif |
|
1543 |
1 |
/* -*- C++ -*- |
|
2 |
* |
|
3 |
* This file is a part of LEMON, a generic C++ optimization library |
|
4 |
* |
|
5 |
* Copyright (C) 2003-2008 |
|
6 |
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
|
7 |
* (Egervary Research Group on Combinatorial Optimization, EGRES). |
|
8 |
* |
|
9 |
* Permission to use, modify and distribute this software is granted |
|
10 |
* provided that this copyright notice appears in all copies. For |
|
11 |
* precise terms see the accompanying LICENSE file. |
|
12 |
* |
|
13 |
* This software is provided "AS IS" with no warranty of any kind, |
|
14 |
* express or implied, and with no claim as to its suitability for any |
|
15 |
* purpose. |
|
16 |
* |
|
17 |
*/ |
|
18 |
|
|
19 |
#ifndef LEMON_DIJKSTRA_H |
|
20 |
#define LEMON_DIJKSTRA_H |
|
21 |
|
|
22 |
///\ingroup shortest_path |
|
23 |
///\file |
|
24 |
///\brief Dijkstra algorithm. |
|
25 |
/// |
|
26 |
|
|
27 |
#include <lemon/list_digraph.h> |
|
28 |
#include <lemon/bin_heap.h> |
|
29 |
#include <lemon/bits/path_dump.h> |
|
30 |
#include <lemon/bits/invalid.h> |
|
31 |
#include <lemon/error.h> |
|
32 |
#include <lemon/maps.h> |
|
33 |
|
|
34 |
|
|
35 |
namespace lemon { |
|
36 |
|
|
37 |
/// \brief Default OperationTraits for the Dijkstra algorithm class. |
|
38 |
/// |
|
39 |
/// It defines all computational operations and constants which are |
|
40 |
/// used in the Dijkstra algorithm. |
|
41 |
template <typename Value> |
|
42 |
struct DijkstraDefaultOperationTraits { |
|
43 |
/// \brief Gives back the zero value of the type. |
|
44 |
static Value zero() { |
|
45 |
return static_cast<Value>(0); |
|
46 |
} |
|
47 |
/// \brief Gives back the sum of the given two elements. |
|
48 |
static Value plus(const Value& left, const Value& right) { |
|
49 |
return left + right; |
|
50 |
} |
|
51 |
/// \brief Gives back true only if the first value less than the second. |
|
52 |
static bool less(const Value& left, const Value& right) { |
|
53 |
return left < right; |
|
54 |
} |
|
55 |
}; |
|
56 |
|
|
57 |
/// \brief Widest path OperationTraits for the Dijkstra algorithm class. |
|
58 |
/// |
|
59 |
/// It defines all computational operations and constants which are |
|
60 |
/// used in the Dijkstra algorithm for widest path computation. |
|
61 |
template <typename Value> |
|
62 |
struct DijkstraWidestPathOperationTraits { |
|
63 |
/// \brief Gives back the maximum value of the type. |
|
64 |
static Value zero() { |
|
65 |
return std::numeric_limits<Value>::max(); |
|
66 |
} |
|
67 |
/// \brief Gives back the minimum of the given two elements. |
|
68 |
static Value plus(const Value& left, const Value& right) { |
|
69 |
return std::min(left, right); |
|
70 |
} |
|
71 |
/// \brief Gives back true only if the first value less than the second. |
|
72 |
static bool less(const Value& left, const Value& right) { |
|
73 |
return left < right; |
|
74 |
} |
|
75 |
}; |
|
76 |
|
|
77 |
///Default traits class of Dijkstra class. |
|
78 |
|
|
79 |
///Default traits class of Dijkstra class. |
|
80 |
///\param GR Digraph type. |
|
81 |
///\param LM Type of length map. |
|
82 |
template<class GR, class LM> |
|
83 |
struct DijkstraDefaultTraits |
|
84 |
{ |
|
85 |
///The digraph type the algorithm runs on. |
|
86 |
typedef GR Digraph; |
|
87 |
///The type of the map that stores the arc lengths. |
|
88 |
|
|
89 |
///The type of the map that stores the arc lengths. |
|
90 |
///It must meet the \ref concepts::ReadMap "ReadMap" concept. |
|
91 |
typedef LM LengthMap; |
|
92 |
//The type of the length of the arcs. |
|
93 |
typedef typename LM::Value Value; |
|
94 |
/// Operation traits for Dijkstra algorithm. |
|
95 |
|
|
96 |
/// It defines the used operation by the algorithm. |
|
97 |
/// \see DijkstraDefaultOperationTraits |
|
98 |
typedef DijkstraDefaultOperationTraits<Value> OperationTraits; |
|
99 |
/// The cross reference type used by heap. |
|
100 |
|
|
101 |
|
|
102 |
/// The cross reference type used by heap. |
|
103 |
/// Usually it is \c Digraph::NodeMap<int>. |
|
104 |
typedef typename Digraph::template NodeMap<int> HeapCrossRef; |
|
105 |
///Instantiates a HeapCrossRef. |
|
106 |
|
|
107 |
///This function instantiates a \c HeapCrossRef. |
|
108 |
/// \param G is the digraph, to which we would like to define the |
|
109 |
/// HeapCrossRef. |
|
110 |
static HeapCrossRef *createHeapCrossRef(const GR &G) |
|
111 |
{ |
|
112 |
return new HeapCrossRef(G); |
|
113 |
} |
|
114 |
|
|
115 |
///The heap type used by Dijkstra algorithm. |
|
116 |
|
|
117 |
///The heap type used by Dijkstra algorithm. |
|
118 |
/// |
|
119 |
///\sa BinHeap |
|
120 |
///\sa Dijkstra |
|
121 |
typedef BinHeap<typename LM::Value, HeapCrossRef, std::less<Value> > Heap; |
|
122 |
|
|
123 |
static Heap *createHeap(HeapCrossRef& R) |
|
124 |
{ |
|
125 |
return new Heap(R); |
|
126 |
} |
|
127 |
|
|
128 |
///\brief The type of the map that stores the last |
|
129 |
///arcs of the shortest paths. |
|
130 |
/// |
|
131 |
///The type of the map that stores the last |
|
132 |
///arcs of the shortest paths. |
|
133 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
134 |
/// |
|
135 |
typedef typename Digraph::template NodeMap<typename GR::Arc> PredMap; |
|
136 |
///Instantiates a PredMap. |
|
137 |
|
|
138 |
///This function instantiates a \c PredMap. |
|
139 |
///\param G is the digraph, to which we would like to define the PredMap. |
|
140 |
///\todo The digraph alone may be insufficient for the initialization |
|
141 |
static PredMap *createPredMap(const GR &G) |
|
142 |
{ |
|
143 |
return new PredMap(G); |
|
144 |
} |
|
145 |
|
|
146 |
///The type of the map that stores whether a nodes is processed. |
|
147 |
|
|
148 |
///The type of the map that stores whether a nodes is processed. |
|
149 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
150 |
///By default it is a NullMap. |
|
151 |
///\todo If it is set to a real map, |
|
152 |
///Dijkstra::processed() should read this. |
|
153 |
///\todo named parameter to set this type, function to read and write. |
|
154 |
typedef NullMap<typename Digraph::Node,bool> ProcessedMap; |
|
155 |
///Instantiates a ProcessedMap. |
|
156 |
|
|
157 |
///This function instantiates a \c ProcessedMap. |
|
158 |
///\param g is the digraph, to which |
|
159 |
///we would like to define the \c ProcessedMap |
|
160 |
#ifdef DOXYGEN |
|
161 |
static ProcessedMap *createProcessedMap(const GR &g) |
|
162 |
#else |
|
163 |
static ProcessedMap *createProcessedMap(const GR &) |
|
164 |
#endif |
|
165 |
{ |
|
166 |
return new ProcessedMap(); |
|
167 |
} |
|
168 |
///The type of the map that stores the dists of the nodes. |
|
169 |
|
|
170 |
///The type of the map that stores the dists of the nodes. |
|
171 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
172 |
/// |
|
173 |
typedef typename Digraph::template NodeMap<typename LM::Value> DistMap; |
|
174 |
///Instantiates a DistMap. |
|
175 |
|
|
176 |
///This function instantiates a \ref DistMap. |
|
177 |
///\param G is the digraph, to which we would like to define the \ref DistMap |
|
178 |
static DistMap *createDistMap(const GR &G) |
|
179 |
{ |
|
180 |
return new DistMap(G); |
|
181 |
} |
|
182 |
}; |
|
183 |
|
|
184 |
///%Dijkstra algorithm class. |
|
185 |
|
|
186 |
/// \ingroup shortest_path |
|
187 |
///This class provides an efficient implementation of %Dijkstra algorithm. |
|
188 |
///The arc lengths are passed to the algorithm using a |
|
189 |
///\ref concepts::ReadMap "ReadMap", |
|
190 |
///so it is easy to change it to any kind of length. |
|
191 |
/// |
|
192 |
///The type of the length is determined by the |
|
193 |
///\ref concepts::ReadMap::Value "Value" of the length map. |
|
194 |
/// |
|
195 |
///It is also possible to change the underlying priority heap. |
|
196 |
/// |
|
197 |
///\param GR The digraph type the algorithm runs on. The default value |
|
198 |
///is \ref ListDigraph. The value of GR is not used directly by |
|
199 |
///Dijkstra, it is only passed to \ref DijkstraDefaultTraits. |
|
200 |
///\param LM This read-only ArcMap determines the lengths of the |
|
201 |
///arcs. It is read once for each arc, so the map may involve in |
|
202 |
///relatively time consuming process to compute the arc length if |
|
203 |
///it is necessary. The default map type is \ref |
|
204 |
///concepts::Digraph::ArcMap "Digraph::ArcMap<int>". The value |
|
205 |
///of LM is not used directly by Dijkstra, it is only passed to \ref |
|
206 |
///DijkstraDefaultTraits. \param TR Traits class to set |
|
207 |
///various data types used by the algorithm. The default traits |
|
208 |
///class is \ref DijkstraDefaultTraits |
|
209 |
///"DijkstraDefaultTraits<GR,LM>". See \ref |
|
210 |
///DijkstraDefaultTraits for the documentation of a Dijkstra traits |
|
211 |
///class. |
|
212 |
/// |
|
213 |
///\author Jacint Szabo and Alpar Juttner |
|
214 |
|
|
215 |
#ifdef DOXYGEN |
|
216 |
template <typename GR, typename LM, typename TR> |
|
217 |
#else |
|
218 |
template <typename GR=ListDigraph, |
|
219 |
typename LM=typename GR::template ArcMap<int>, |
|
220 |
typename TR=DijkstraDefaultTraits<GR,LM> > |
|
221 |
#endif |
|
222 |
class Dijkstra { |
|
223 |
public: |
|
224 |
/** |
|
225 |
* \brief \ref Exception for uninitialized parameters. |
|
226 |
* |
|
227 |
* This error represents problems in the initialization |
|
228 |
* of the parameters of the algorithms. |
|
229 |
*/ |
|
230 |
class UninitializedParameter : public lemon::UninitializedParameter { |
|
231 |
public: |
|
232 |
virtual const char* what() const throw() { |
|
233 |
return "lemon::Dijkstra::UninitializedParameter"; |
|
234 |
} |
|
235 |
}; |
|
236 |
|
|
237 |
typedef TR Traits; |
|
238 |
///The type of the underlying digraph. |
|
239 |
typedef typename TR::Digraph Digraph; |
|
240 |
///\e |
|
241 |
typedef typename Digraph::Node Node; |
|
242 |
///\e |
|
243 |
typedef typename Digraph::NodeIt NodeIt; |
|
244 |
///\e |
|
245 |
typedef typename Digraph::Arc Arc; |
|
246 |
///\e |
|
247 |
typedef typename Digraph::OutArcIt OutArcIt; |
|
248 |
|
|
249 |
///The type of the length of the arcs. |
|
250 |
typedef typename TR::LengthMap::Value Value; |
|
251 |
///The type of the map that stores the arc lengths. |
|
252 |
typedef typename TR::LengthMap LengthMap; |
|
253 |
///\brief The type of the map that stores the last |
|
254 |
///arcs of the shortest paths. |
|
255 |
typedef typename TR::PredMap PredMap; |
|
256 |
///The type of the map indicating if a node is processed. |
|
257 |
typedef typename TR::ProcessedMap ProcessedMap; |
|
258 |
///The type of the map that stores the dists of the nodes. |
|
259 |
typedef typename TR::DistMap DistMap; |
|
260 |
///The cross reference type used for the current heap. |
|
261 |
typedef typename TR::HeapCrossRef HeapCrossRef; |
|
262 |
///The heap type used by the dijkstra algorithm. |
|
263 |
typedef typename TR::Heap Heap; |
|
264 |
///The operation traits. |
|
265 |
typedef typename TR::OperationTraits OperationTraits; |
|
266 |
private: |
|
267 |
/// Pointer to the underlying digraph. |
|
268 |
const Digraph *G; |
|
269 |
/// Pointer to the length map |
|
270 |
const LengthMap *length; |
|
271 |
///Pointer to the map of predecessors arcs. |
|
272 |
PredMap *_pred; |
|
273 |
///Indicates if \ref _pred is locally allocated (\c true) or not. |
|
274 |
bool local_pred; |
|
275 |
///Pointer to the map of distances. |
|
276 |
DistMap *_dist; |
|
277 |
///Indicates if \ref _dist is locally allocated (\c true) or not. |
|
278 |
bool local_dist; |
|
279 |
///Pointer to the map of processed status of the nodes. |
|
280 |
ProcessedMap *_processed; |
|
281 |
///Indicates if \ref _processed is locally allocated (\c true) or not. |
|
282 |
bool local_processed; |
|
283 |
///Pointer to the heap cross references. |
|
284 |
HeapCrossRef *_heap_cross_ref; |
|
285 |
///Indicates if \ref _heap_cross_ref is locally allocated (\c true) or not. |
|
286 |
bool local_heap_cross_ref; |
|
287 |
///Pointer to the heap. |
|
288 |
Heap *_heap; |
|
289 |
///Indicates if \ref _heap is locally allocated (\c true) or not. |
|
290 |
bool local_heap; |
|
291 |
|
|
292 |
///Creates the maps if necessary. |
|
293 |
|
|
294 |
///\todo Better memory allocation (instead of new). |
|
295 |
void create_maps() |
|
296 |
{ |
|
297 |
if(!_pred) { |
|
298 |
local_pred = true; |
|
299 |
_pred = Traits::createPredMap(*G); |
|
300 |
} |
|
301 |
if(!_dist) { |
|
302 |
local_dist = true; |
|
303 |
_dist = Traits::createDistMap(*G); |
|
304 |
} |
|
305 |
if(!_processed) { |
|
306 |
local_processed = true; |
|
307 |
_processed = Traits::createProcessedMap(*G); |
|
308 |
} |
|
309 |
if (!_heap_cross_ref) { |
|
310 |
local_heap_cross_ref = true; |
|
311 |
_heap_cross_ref = Traits::createHeapCrossRef(*G); |
|
312 |
} |
|
313 |
if (!_heap) { |
|
314 |
local_heap = true; |
|
315 |
_heap = Traits::createHeap(*_heap_cross_ref); |
|
316 |
} |
|
317 |
} |
|
318 |
|
|
319 |
public : |
|
320 |
|
|
321 |
typedef Dijkstra Create; |
|
322 |
|
|
323 |
///\name Named template parameters |
|
324 |
|
|
325 |
///@{ |
|
326 |
|
|
327 |
template <class T> |
|
328 |
struct DefPredMapTraits : public Traits { |
|
329 |
typedef T PredMap; |
|
330 |
static PredMap *createPredMap(const Digraph &) |
|
331 |
{ |
|
332 |
throw UninitializedParameter(); |
|
333 |
} |
|
334 |
}; |
|
335 |
///\ref named-templ-param "Named parameter" for setting PredMap type |
|
336 |
|
|
337 |
///\ref named-templ-param "Named parameter" for setting PredMap type |
|
338 |
/// |
|
339 |
template <class T> |
|
340 |
struct DefPredMap |
|
341 |
: public Dijkstra< Digraph, LengthMap, DefPredMapTraits<T> > { |
|
342 |
typedef Dijkstra< Digraph, LengthMap, DefPredMapTraits<T> > Create; |
|
343 |
}; |
|
344 |
|
|
345 |
template <class T> |
|
346 |
struct DefDistMapTraits : public Traits { |
|
347 |
typedef T DistMap; |
|
348 |
static DistMap *createDistMap(const Digraph &) |
|
349 |
{ |
|
350 |
throw UninitializedParameter(); |
|
351 |
} |
|
352 |
}; |
|
353 |
///\ref named-templ-param "Named parameter" for setting DistMap type |
|
354 |
|
|
355 |
///\ref named-templ-param "Named parameter" for setting DistMap type |
|
356 |
/// |
|
357 |
template <class T> |
|
358 |
struct DefDistMap |
|
359 |
: public Dijkstra< Digraph, LengthMap, DefDistMapTraits<T> > { |
|
360 |
typedef Dijkstra< Digraph, LengthMap, DefDistMapTraits<T> > Create; |
|
361 |
}; |
|
362 |
|
|
363 |
template <class T> |
|
364 |
struct DefProcessedMapTraits : public Traits { |
|
365 |
typedef T ProcessedMap; |
|
366 |
static ProcessedMap *createProcessedMap(const Digraph &G) |
|
367 |
{ |
|
368 |
throw UninitializedParameter(); |
|
369 |
} |
|
370 |
}; |
|
371 |
///\ref named-templ-param "Named parameter" for setting ProcessedMap type |
|
372 |
|
|
373 |
///\ref named-templ-param "Named parameter" for setting ProcessedMap type |
|
374 |
/// |
|
375 |
template <class T> |
|
376 |
struct DefProcessedMap |
|
377 |
: public Dijkstra< Digraph, LengthMap, DefProcessedMapTraits<T> > { |
|
378 |
typedef Dijkstra< Digraph, LengthMap, DefProcessedMapTraits<T> > Create; |
|
379 |
}; |
|
380 |
|
|
381 |
struct DefDigraphProcessedMapTraits : public Traits { |
|
382 |
typedef typename Digraph::template NodeMap<bool> ProcessedMap; |
|
383 |
static ProcessedMap *createProcessedMap(const Digraph &G) |
|
384 |
{ |
|
385 |
return new ProcessedMap(G); |
|
386 |
} |
|
387 |
}; |
|
388 |
///\brief \ref named-templ-param "Named parameter" |
|
389 |
///for setting the ProcessedMap type to be Digraph::NodeMap<bool>. |
|
390 |
/// |
|
391 |
///\ref named-templ-param "Named parameter" |
|
392 |
///for setting the ProcessedMap type to be Digraph::NodeMap<bool>. |
|
393 |
///If you don't set it explicitely, it will be automatically allocated. |
|
394 |
template <class T> |
|
395 |
struct DefProcessedMapToBeDefaultMap |
|
396 |
: public Dijkstra< Digraph, LengthMap, DefDigraphProcessedMapTraits> { |
|
397 |
typedef Dijkstra< Digraph, LengthMap, DefDigraphProcessedMapTraits> Create; |
|
398 |
}; |
|
399 |
|
|
400 |
template <class H, class CR> |
|
401 |
struct DefHeapTraits : public Traits { |
|
402 |
typedef CR HeapCrossRef; |
|
403 |
typedef H Heap; |
|
404 |
static HeapCrossRef *createHeapCrossRef(const Digraph &) { |
|
405 |
throw UninitializedParameter(); |
|
406 |
} |
|
407 |
static Heap *createHeap(HeapCrossRef &) |
|
408 |
{ |
|
409 |
throw UninitializedParameter(); |
|
410 |
} |
|
411 |
}; |
|
412 |
///\brief \ref named-templ-param "Named parameter" for setting |
|
413 |
///heap and cross reference type |
|
414 |
/// |
|
415 |
///\ref named-templ-param "Named parameter" for setting heap and cross |
|
416 |
///reference type |
|
417 |
/// |
|
418 |
template <class H, class CR = typename Digraph::template NodeMap<int> > |
|
419 |
struct DefHeap |
|
420 |
: public Dijkstra< Digraph, LengthMap, DefHeapTraits<H, CR> > { |
|
421 |
typedef Dijkstra< Digraph, LengthMap, DefHeapTraits<H, CR> > Create; |
|
422 |
}; |
|
423 |
|
|
424 |
template <class H, class CR> |
|
425 |
struct DefStandardHeapTraits : public Traits { |
|
426 |
typedef CR HeapCrossRef; |
|
427 |
typedef H Heap; |
|
428 |
static HeapCrossRef *createHeapCrossRef(const Digraph &G) { |
|
429 |
return new HeapCrossRef(G); |
|
430 |
} |
|
431 |
static Heap *createHeap(HeapCrossRef &R) |
|
432 |
{ |
|
433 |
return new Heap(R); |
|
434 |
} |
|
435 |
}; |
|
436 |
///\brief \ref named-templ-param "Named parameter" for setting |
|
437 |
///heap and cross reference type with automatic allocation |
|
438 |
/// |
|
439 |
///\ref named-templ-param "Named parameter" for setting heap and cross |
|
440 |
///reference type. It can allocate the heap and the cross reference |
|
441 |
///object if the cross reference's constructor waits for the digraph as |
|
442 |
///parameter and the heap's constructor waits for the cross reference. |
|
443 |
template <class H, class CR = typename Digraph::template NodeMap<int> > |
|
444 |
struct DefStandardHeap |
|
445 |
: public Dijkstra< Digraph, LengthMap, DefStandardHeapTraits<H, CR> > { |
|
446 |
typedef Dijkstra< Digraph, LengthMap, DefStandardHeapTraits<H, CR> > |
|
447 |
Create; |
|
448 |
}; |
|
449 |
|
|
450 |
template <class T> |
|
451 |
struct DefOperationTraitsTraits : public Traits { |
|
452 |
typedef T OperationTraits; |
|
453 |
}; |
|
454 |
|
|
455 |
/// \brief \ref named-templ-param "Named parameter" for setting |
|
456 |
/// OperationTraits type |
|
457 |
/// |
|
458 |
/// \ref named-templ-param "Named parameter" for setting OperationTraits |
|
459 |
/// type |
|
460 |
template <class T> |
|
461 |
struct DefOperationTraits |
|
462 |
: public Dijkstra<Digraph, LengthMap, DefOperationTraitsTraits<T> > { |
|
463 |
typedef Dijkstra<Digraph, LengthMap, DefOperationTraitsTraits<T> > |
|
464 |
Create; |
|
465 |
}; |
|
466 |
|
|
467 |
///@} |
|
468 |
|
|
469 |
|
|
470 |
protected: |
|
471 |
|
|
472 |
Dijkstra() {} |
|
473 |
|
|
474 |
public: |
|
475 |
|
|
476 |
///Constructor. |
|
477 |
|
|
478 |
///\param _G the digraph the algorithm will run on. |
|
479 |
///\param _length the length map used by the algorithm. |
|
480 |
Dijkstra(const Digraph& _G, const LengthMap& _length) : |
|
481 |
G(&_G), length(&_length), |
|
482 |
_pred(NULL), local_pred(false), |
|
483 |
_dist(NULL), local_dist(false), |
|
484 |
_processed(NULL), local_processed(false), |
|
485 |
_heap_cross_ref(NULL), local_heap_cross_ref(false), |
|
486 |
_heap(NULL), local_heap(false) |
|
487 |
{ } |
|
488 |
|
|
489 |
///Destructor. |
|
490 |
~Dijkstra() |
|
491 |
{ |
|
492 |
if(local_pred) delete _pred; |
|
493 |
if(local_dist) delete _dist; |
|
494 |
if(local_processed) delete _processed; |
|
495 |
if(local_heap_cross_ref) delete _heap_cross_ref; |
|
496 |
if(local_heap) delete _heap; |
|
497 |
} |
|
498 |
|
|
499 |
///Sets the length map. |
|
500 |
|
|
501 |
///Sets the length map. |
|
502 |
///\return <tt> (*this) </tt> |
|
503 |
Dijkstra &lengthMap(const LengthMap &m) |
|
504 |
{ |
|
505 |
length = &m; |
|
506 |
return *this; |
|
507 |
} |
|
508 |
|
|
509 |
///Sets the map storing the predecessor arcs. |
|
510 |
|
|
511 |
///Sets the map storing the predecessor arcs. |
|
512 |
///If you don't use this function before calling \ref run(), |
|
513 |
///it will allocate one. The destuctor deallocates this |
|
514 |
///automatically allocated map, of course. |
|
515 |
///\return <tt> (*this) </tt> |
|
516 |
Dijkstra &predMap(PredMap &m) |
|
517 |
{ |
|
518 |
if(local_pred) { |
|
519 |
delete _pred; |
|
520 |
local_pred=false; |
|
521 |
} |
|
522 |
_pred = &m; |
|
523 |
return *this; |
|
524 |
} |
|
525 |
|
|
526 |
///Sets the map storing the distances calculated by the algorithm. |
|
527 |
|
|
528 |
///Sets the map storing the distances calculated by the algorithm. |
|
529 |
///If you don't use this function before calling \ref run(), |
|
530 |
///it will allocate one. The destuctor deallocates this |
|
531 |
///automatically allocated map, of course. |
|
532 |
///\return <tt> (*this) </tt> |
|
533 |
Dijkstra &distMap(DistMap &m) |
|
534 |
{ |
|
535 |
if(local_dist) { |
|
536 |
delete _dist; |
|
537 |
local_dist=false; |
|
538 |
} |
|
539 |
_dist = &m; |
|
540 |
return *this; |
|
541 |
} |
|
542 |
|
|
543 |
///Sets the heap and the cross reference used by algorithm. |
|
544 |
|
|
545 |
///Sets the heap and the cross reference used by algorithm. |
|
546 |
///If you don't use this function before calling \ref run(), |
|
547 |
///it will allocate one. The destuctor deallocates this |
|
548 |
///automatically allocated heap and cross reference, of course. |
|
549 |
///\return <tt> (*this) </tt> |
|
550 |
Dijkstra &heap(Heap& hp, HeapCrossRef &cr) |
|
551 |
{ |
|
552 |
if(local_heap_cross_ref) { |
|
553 |
delete _heap_cross_ref; |
|
554 |
local_heap_cross_ref=false; |
|
555 |
} |
|
556 |
_heap_cross_ref = &cr; |
|
557 |
if(local_heap) { |
|
558 |
delete _heap; |
|
559 |
local_heap=false; |
|
560 |
} |
|
561 |
_heap = &hp; |
|
562 |
return *this; |
|
563 |
} |
|
564 |
|
|
565 |
private: |
|
566 |
void finalizeNodeData(Node v,Value dst) |
|
567 |
{ |
|
568 |
_processed->set(v,true); |
|
569 |
_dist->set(v, dst); |
|
570 |
} |
|
571 |
|
|
572 |
public: |
|
573 |
|
|
574 |
typedef PredMapPath<Digraph, PredMap> Path; |
|
575 |
|
|
576 |
///\name Execution control |
|
577 |
///The simplest way to execute the algorithm is to use |
|
578 |
///one of the member functions called \c run(...). |
|
579 |
///\n |
|
580 |
///If you need more control on the execution, |
|
581 |
///first you must call \ref init(), then you can add several source nodes |
|
582 |
///with \ref addSource(). |
|
583 |
///Finally \ref start() will perform the actual path |
|
584 |
///computation. |
|
585 |
|
|
586 |
///@{ |
|
587 |
|
|
588 |
///Initializes the internal data structures. |
|
589 |
|
|
590 |
///Initializes the internal data structures. |
|
591 |
/// |
|
592 |
void init() |
|
593 |
{ |
|
594 |
create_maps(); |
|
595 |
_heap->clear(); |
|
596 |
for ( NodeIt u(*G) ; u!=INVALID ; ++u ) { |
|
597 |
_pred->set(u,INVALID); |
|
598 |
_processed->set(u,false); |
|
599 |
_heap_cross_ref->set(u,Heap::PRE_HEAP); |
|
600 |
} |
|
601 |
} |
|
602 |
|
|
603 |
///Adds a new source node. |
|
604 |
|
|
605 |
///Adds a new source node to the priority heap. |
|
606 |
/// |
|
607 |
///The optional second parameter is the initial distance of the node. |
|
608 |
/// |
|
609 |
///It checks if the node has already been added to the heap and |
|
610 |
///it is pushed to the heap only if either it was not in the heap |
|
611 |
///or the shortest path found till then is shorter than \c dst. |
|
612 |
void addSource(Node s,Value dst=OperationTraits::zero()) |
|
613 |
{ |
|
614 |
if(_heap->state(s) != Heap::IN_HEAP) { |
|
615 |
_heap->push(s,dst); |
|
616 |
} else if(OperationTraits::less((*_heap)[s], dst)) { |
|
617 |
_heap->set(s,dst); |
|
618 |
_pred->set(s,INVALID); |
|
619 |
} |
|
620 |
} |
|
621 |
|
|
622 |
///Processes the next node in the priority heap |
|
623 |
|
|
624 |
///Processes the next node in the priority heap. |
|
625 |
/// |
|
626 |
///\return The processed node. |
|
627 |
/// |
|
628 |
///\warning The priority heap must not be empty! |
|
629 |
Node processNextNode() |
|
630 |
{ |
|
631 |
Node v=_heap->top(); |
|
632 |
Value oldvalue=_heap->prio(); |
|
633 |
_heap->pop(); |
|
634 |
finalizeNodeData(v,oldvalue); |
|
635 |
|
|
636 |
for(OutArcIt e(*G,v); e!=INVALID; ++e) { |
|
637 |
Node w=G->target(e); |
|
638 |
switch(_heap->state(w)) { |
|
639 |
case Heap::PRE_HEAP: |
|
640 |
_heap->push(w,OperationTraits::plus(oldvalue, (*length)[e])); |
|
641 |
_pred->set(w,e); |
|
642 |
break; |
|
643 |
case Heap::IN_HEAP: |
|
644 |
{ |
|
645 |
Value newvalue = OperationTraits::plus(oldvalue, (*length)[e]); |
|
646 |
if ( OperationTraits::less(newvalue, (*_heap)[w]) ) { |
|
647 |
_heap->decrease(w, newvalue); |
|
648 |
_pred->set(w,e); |
|
649 |
} |
|
650 |
} |
|
651 |
break; |
|
652 |
case Heap::POST_HEAP: |
|
653 |
break; |
|
654 |
} |
|
655 |
} |
|
656 |
return v; |
|
657 |
} |
|
658 |
|
|
659 |
///Next node to be processed. |
|
660 |
|
|
661 |
///Next node to be processed. |
|
662 |
/// |
|
663 |
///\return The next node to be processed or INVALID if the priority heap |
|
664 |
/// is empty. |
|
665 |
Node nextNode() |
|
666 |
{ |
|
667 |
return !_heap->empty()?_heap->top():INVALID; |
|
668 |
} |
|
669 |
|
|
670 |
///\brief Returns \c false if there are nodes |
|
671 |
///to be processed in the priority heap |
|
672 |
/// |
|
673 |
///Returns \c false if there are nodes |
|
674 |
///to be processed in the priority heap |
|
675 |
bool emptyQueue() { return _heap->empty(); } |
|
676 |
///Returns the number of the nodes to be processed in the priority heap |
|
677 |
|
|
678 |
///Returns the number of the nodes to be processed in the priority heap |
|
679 |
/// |
|
680 |
int queueSize() { return _heap->size(); } |
|
681 |
|
|
682 |
///Executes the algorithm. |
|
683 |
|
|
684 |
///Executes the algorithm. |
|
685 |
/// |
|
686 |
///\pre init() must be called and at least one node should be added |
|
687 |
///with addSource() before using this function. |
|
688 |
/// |
|
689 |
///This method runs the %Dijkstra algorithm from the root node(s) |
|
690 |
///in order to |
|
691 |
///compute the |
|
692 |
///shortest path to each node. The algorithm computes |
|
693 |
///- The shortest path tree. |
|
694 |
///- The distance of each node from the root(s). |
|
695 |
/// |
|
696 |
void start() |
|
697 |
{ |
|
698 |
while ( !_heap->empty() ) processNextNode(); |
|
699 |
} |
|
700 |
|
|
701 |
///Executes the algorithm until \c dest is reached. |
|
702 |
|
|
703 |
///Executes the algorithm until \c dest is reached. |
|
704 |
/// |
|
705 |
///\pre init() must be called and at least one node should be added |
|
706 |
///with addSource() before using this function. |
|
707 |
/// |
|
708 |
///This method runs the %Dijkstra algorithm from the root node(s) |
|
709 |
///in order to |
|
710 |
///compute the |
|
711 |
///shortest path to \c dest. The algorithm computes |
|
712 |
///- The shortest path to \c dest. |
|
713 |
///- The distance of \c dest from the root(s). |
|
714 |
/// |
|
715 |
void start(Node dest) |
|
716 |
{ |
|
717 |
while ( !_heap->empty() && _heap->top()!=dest ) processNextNode(); |
|
718 |
if ( !_heap->empty() ) finalizeNodeData(_heap->top(),_heap->prio()); |
|
719 |
} |
|
720 |
|
|
721 |
///Executes the algorithm until a condition is met. |
|
722 |
|
|
723 |
///Executes the algorithm until a condition is met. |
|
724 |
/// |
|
725 |
///\pre init() must be called and at least one node should be added |
|
726 |
///with addSource() before using this function. |
|
727 |
/// |
|
728 |
///\param nm must be a bool (or convertible) node map. The algorithm |
|
729 |
///will stop when it reaches a node \c v with <tt>nm[v]</tt> true. |
|
730 |
/// |
|
731 |
///\return The reached node \c v with <tt>nm[v]</tt> true or |
|
732 |
///\c INVALID if no such node was found. |
|
733 |
template<class NodeBoolMap> |
|
734 |
Node start(const NodeBoolMap &nm) |
|
735 |
{ |
|
736 |
while ( !_heap->empty() && !nm[_heap->top()] ) processNextNode(); |
|
737 |
if ( _heap->empty() ) return INVALID; |
|
738 |
finalizeNodeData(_heap->top(),_heap->prio()); |
|
739 |
return _heap->top(); |
|
740 |
} |
|
741 |
|
|
742 |
///Runs %Dijkstra algorithm from node \c s. |
|
743 |
|
|
744 |
///This method runs the %Dijkstra algorithm from a root node \c s |
|
745 |
///in order to |
|
746 |
///compute the |
|
747 |
///shortest path to each node. The algorithm computes |
|
748 |
///- The shortest path tree. |
|
749 |
///- The distance of each node from the root. |
|
750 |
/// |
|
751 |
///\note d.run(s) is just a shortcut of the following code. |
|
752 |
///\code |
|
753 |
/// d.init(); |
|
754 |
/// d.addSource(s); |
|
755 |
/// d.start(); |
|
756 |
///\endcode |
|
757 |
void run(Node s) { |
|
758 |
init(); |
|
759 |
addSource(s); |
|
760 |
start(); |
|
761 |
} |
|
762 |
|
|
763 |
///Finds the shortest path between \c s and \c t. |
|
764 |
|
|
765 |
///Finds the shortest path between \c s and \c t. |
|
766 |
/// |
|
767 |
///\return The length of the shortest s---t path if there exists one, |
|
768 |
///0 otherwise. |
|
769 |
///\note Apart from the return value, d.run(s) is |
|
770 |
///just a shortcut of the following code. |
|
771 |
///\code |
|
772 |
/// d.init(); |
|
773 |
/// d.addSource(s); |
|
774 |
/// d.start(t); |
|
775 |
///\endcode |
|
776 |
Value run(Node s,Node t) { |
|
777 |
init(); |
|
778 |
addSource(s); |
|
779 |
start(t); |
|
780 |
return (*_pred)[t]==INVALID?OperationTraits::zero():(*_dist)[t]; |
|
781 |
} |
|
782 |
|
|
783 |
///@} |
|
784 |
|
|
785 |
///\name Query Functions |
|
786 |
///The result of the %Dijkstra algorithm can be obtained using these |
|
787 |
///functions.\n |
|
788 |
///Before the use of these functions, |
|
789 |
///either run() or start() must be called. |
|
790 |
|
|
791 |
///@{ |
|
792 |
|
|
793 |
///Gives back the shortest path. |
|
794 |
|
|
795 |
///Gives back the shortest path. |
|
796 |
///\pre The \c t should be reachable from the source. |
|
797 |
Path path(Node t) |
|
798 |
{ |
|
799 |
return Path(*G, *_pred, t); |
|
800 |
} |
|
801 |
|
|
802 |
///The distance of a node from the root. |
|
803 |
|
|
804 |
///Returns the distance of a node from the root. |
|
805 |
///\pre \ref run() must be called before using this function. |
|
806 |
///\warning If node \c v in unreachable from the root the return value |
|
807 |
///of this funcion is undefined. |
|
808 |
Value dist(Node v) const { return (*_dist)[v]; } |
|
809 |
|
|
810 |
///The current distance of a node from the root. |
|
811 |
|
|
812 |
///Returns the current distance of a node from the root. |
|
813 |
///It may be decreased in the following processes. |
|
814 |
///\pre \c node should be reached but not processed |
|
815 |
Value currentDist(Node v) const { return (*_heap)[v]; } |
|
816 |
|
|
817 |
///Returns the 'previous arc' of the shortest path tree. |
|
818 |
|
|
819 |
///For a node \c v it returns the 'previous arc' of the shortest path tree, |
|
820 |
///i.e. it returns the last arc of a shortest path from the root to \c |
|
821 |
///v. It is \ref INVALID |
|
822 |
///if \c v is unreachable from the root or if \c v=s. The |
|
823 |
///shortest path tree used here is equal to the shortest path tree used in |
|
824 |
///\ref predNode(). \pre \ref run() must be called before using |
|
825 |
///this function. |
|
826 |
Arc predArc(Node v) const { return (*_pred)[v]; } |
|
827 |
|
|
828 |
///Returns the 'previous node' of the shortest path tree. |
|
829 |
|
|
830 |
///For a node \c v it returns the 'previous node' of the shortest path tree, |
|
831 |
///i.e. it returns the last but one node from a shortest path from the |
|
832 |
///root to \c /v. It is INVALID if \c v is unreachable from the root or if |
|
833 |
///\c v=s. The shortest path tree used here is equal to the shortest path |
|
834 |
///tree used in \ref predArc(). \pre \ref run() must be called before |
|
835 |
///using this function. |
|
836 |
Node predNode(Node v) const { return (*_pred)[v]==INVALID ? INVALID: |
|
837 |
G->source((*_pred)[v]); } |
|
838 |
|
|
839 |
///Returns a reference to the NodeMap of distances. |
|
840 |
|
|
841 |
///Returns a reference to the NodeMap of distances. \pre \ref run() must |
|
842 |
///be called before using this function. |
|
843 |
const DistMap &distMap() const { return *_dist;} |
|
844 |
|
|
845 |
///Returns a reference to the shortest path tree map. |
|
846 |
|
|
847 |
///Returns a reference to the NodeMap of the arcs of the |
|
848 |
///shortest path tree. |
|
849 |
///\pre \ref run() must be called before using this function. |
|
850 |
const PredMap &predMap() const { return *_pred;} |
|
851 |
|
|
852 |
///Checks if a node is reachable from the root. |
|
853 |
|
|
854 |
///Returns \c true if \c v is reachable from the root. |
|
855 |
///\warning The source nodes are inditated as unreached. |
|
856 |
///\pre \ref run() must be called before using this function. |
|
857 |
/// |
|
858 |
bool reached(Node v) { return (*_heap_cross_ref)[v] != Heap::PRE_HEAP; } |
|
859 |
|
|
860 |
///Checks if a node is processed. |
|
861 |
|
|
862 |
///Returns \c true if \c v is processed, i.e. the shortest |
|
863 |
///path to \c v has already found. |
|
864 |
///\pre \ref run() must be called before using this function. |
|
865 |
/// |
|
866 |
bool processed(Node v) { return (*_heap_cross_ref)[v] == Heap::POST_HEAP; } |
|
867 |
|
|
868 |
///@} |
|
869 |
}; |
|
870 |
|
|
871 |
|
|
872 |
|
|
873 |
|
|
874 |
|
|
875 |
///Default traits class of Dijkstra function. |
|
876 |
|
|
877 |
///Default traits class of Dijkstra function. |
|
878 |
///\param GR Digraph type. |
|
879 |
///\param LM Type of length map. |
|
880 |
template<class GR, class LM> |
|
881 |
struct DijkstraWizardDefaultTraits |
|
882 |
{ |
|
883 |
///The digraph type the algorithm runs on. |
|
884 |
typedef GR Digraph; |
|
885 |
///The type of the map that stores the arc lengths. |
|
886 |
|
|
887 |
///The type of the map that stores the arc lengths. |
|
888 |
///It must meet the \ref concepts::ReadMap "ReadMap" concept. |
|
889 |
typedef LM LengthMap; |
|
890 |
//The type of the length of the arcs. |
|
891 |
typedef typename LM::Value Value; |
|
892 |
/// Operation traits for Dijkstra algorithm. |
|
893 |
|
|
894 |
/// It defines the used operation by the algorithm. |
|
895 |
/// \see DijkstraDefaultOperationTraits |
|
896 |
typedef DijkstraDefaultOperationTraits<Value> OperationTraits; |
|
897 |
///The heap type used by Dijkstra algorithm. |
|
898 |
|
|
899 |
/// The cross reference type used by heap. |
|
900 |
|
|
901 |
/// The cross reference type used by heap. |
|
902 |
/// Usually it is \c Digraph::NodeMap<int>. |
|
903 |
typedef typename Digraph::template NodeMap<int> HeapCrossRef; |
|
904 |
///Instantiates a HeapCrossRef. |
|
905 |
|
|
906 |
///This function instantiates a \ref HeapCrossRef. |
|
907 |
/// \param G is the digraph, to which we would like to define the |
|
908 |
/// HeapCrossRef. |
|
909 |
/// \todo The digraph alone may be insufficient for the initialization |
|
910 |
static HeapCrossRef *createHeapCrossRef(const GR &G) |
|
911 |
{ |
|
912 |
return new HeapCrossRef(G); |
|
913 |
} |
|
914 |
|
|
915 |
///The heap type used by Dijkstra algorithm. |
|
916 |
|
|
917 |
///The heap type used by Dijkstra algorithm. |
|
918 |
/// |
|
919 |
///\sa BinHeap |
|
920 |
///\sa Dijkstra |
|
921 |
typedef BinHeap<typename LM::Value, typename GR::template NodeMap<int>, |
|
922 |
std::less<Value> > Heap; |
|
923 |
|
|
924 |
static Heap *createHeap(HeapCrossRef& R) |
|
925 |
{ |
|
926 |
return new Heap(R); |
|
927 |
} |
|
928 |
|
|
929 |
///\brief The type of the map that stores the last |
|
930 |
///arcs of the shortest paths. |
|
931 |
/// |
|
932 |
///The type of the map that stores the last |
|
933 |
///arcs of the shortest paths. |
|
934 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
935 |
/// |
|
936 |
typedef NullMap <typename GR::Node,typename GR::Arc> PredMap; |
|
937 |
///Instantiates a PredMap. |
|
938 |
|
|
939 |
///This function instantiates a \ref PredMap. |
|
940 |
///\param g is the digraph, to which we would like to define the PredMap. |
|
941 |
///\todo The digraph alone may be insufficient for the initialization |
|
942 |
#ifdef DOXYGEN |
|
943 |
static PredMap *createPredMap(const GR &g) |
|
944 |
#else |
|
945 |
static PredMap *createPredMap(const GR &) |
|
946 |
#endif |
|
947 |
{ |
|
948 |
return new PredMap(); |
|
949 |
} |
|
950 |
///The type of the map that stores whether a nodes is processed. |
|
951 |
|
|
952 |
///The type of the map that stores whether a nodes is processed. |
|
953 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
954 |
///By default it is a NullMap. |
|
955 |
///\todo If it is set to a real map, |
|
956 |
///Dijkstra::processed() should read this. |
|
957 |
///\todo named parameter to set this type, function to read and write. |
|
958 |
typedef NullMap<typename Digraph::Node,bool> ProcessedMap; |
|
959 |
///Instantiates a ProcessedMap. |
|
960 |
|
|
961 |
///This function instantiates a \ref ProcessedMap. |
|
962 |
///\param g is the digraph, to which |
|
963 |
///we would like to define the \ref ProcessedMap |
|
964 |
#ifdef DOXYGEN |
|
965 |
static ProcessedMap *createProcessedMap(const GR &g) |
|
966 |
#else |
|
967 |
static ProcessedMap *createProcessedMap(const GR &) |
|
968 |
#endif |
|
969 |
{ |
|
970 |
return new ProcessedMap(); |
|
971 |
} |
|
972 |
///The type of the map that stores the dists of the nodes. |
|
973 |
|
|
974 |
///The type of the map that stores the dists of the nodes. |
|
975 |
///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
|
976 |
/// |
|
977 |
typedef NullMap<typename Digraph::Node,typename LM::Value> DistMap; |
|
978 |
///Instantiates a DistMap. |
|
979 |
|
|
980 |
///This function instantiates a \ref DistMap. |
|
981 |
///\param g is the digraph, to which we would like to define the \ref DistMap |
|
982 |
#ifdef DOXYGEN |
|
983 |
static DistMap *createDistMap(const GR &g) |
|
984 |
#else |
|
985 |
static DistMap *createDistMap(const GR &) |
|
986 |
#endif |
|
987 |
{ |
|
988 |
return new DistMap(); |
|
989 |
} |
|
990 |
}; |
|
991 |
|
|
992 |
/// Default traits used by \ref DijkstraWizard |
|
993 |
|
|
994 |
/// To make it easier to use Dijkstra algorithm |
|
995 |
///we have created a wizard class. |
|
996 |
/// This \ref DijkstraWizard class needs default traits, |
|
997 |
///as well as the \ref Dijkstra class. |
|
998 |
/// The \ref DijkstraWizardBase is a class to be the default traits of the |
|
999 |
/// \ref DijkstraWizard class. |
|
1000 |
/// \todo More named parameters are required... |
|
1001 |
template<class GR,class LM> |
|
1002 |
class DijkstraWizardBase : public DijkstraWizardDefaultTraits<GR,LM> |
|
1003 |
{ |
|
1004 |
|
|
1005 |
typedef DijkstraWizardDefaultTraits<GR,LM> Base; |
|
1006 |
protected: |
|
1007 |
/// Type of the nodes in the digraph. |
|
1008 |
typedef typename Base::Digraph::Node Node; |
|
1009 |
|
|
1010 |
/// Pointer to the underlying digraph. |
|
1011 |
void *_g; |
|
1012 |
/// Pointer to the length map |
|
1013 |
void *_length; |
|
1014 |
///Pointer to the map of predecessors arcs. |
|
1015 |
void *_pred; |
|
1016 |
///Pointer to the map of distances. |
|
1017 |
void *_dist; |
|
1018 |
///Pointer to the source node. |
|
1019 |
Node _source; |
|
1020 |
|
|
1021 |
public: |
|
1022 |
/// Constructor. |
|
1023 |
|
|
1024 |
/// This constructor does not require parameters, therefore it initiates |
|
1025 |
/// all of the attributes to default values (0, INVALID). |
|
1026 |
DijkstraWizardBase() : _g(0), _length(0), _pred(0), |
|
1027 |
_dist(0), _source(INVALID) {} |
|
1028 |
|
|
1029 |
/// Constructor. |
|
1030 |
|
|
1031 |
/// This constructor requires some parameters, |
|
1032 |
/// listed in the parameters list. |
|
1033 |
/// Others are initiated to 0. |
|
1034 |
/// \param g is the initial value of \ref _g |
|
1035 |
/// \param l is the initial value of \ref _length |
|
1036 |
/// \param s is the initial value of \ref _source |
|
1037 |
DijkstraWizardBase(const GR &g,const LM &l, Node s=INVALID) : |
|
1038 |
_g(reinterpret_cast<void*>(const_cast<GR*>(&g))), |
|
1039 |
_length(reinterpret_cast<void*>(const_cast<LM*>(&l))), |
|
1040 |
_pred(0), _dist(0), _source(s) {} |
|
1041 |
|
|
1042 |
}; |
|
1043 |
|
|
1044 |
/// A class to make the usage of Dijkstra algorithm easier |
|
1045 |
|
|
1046 |
/// This class is created to make it easier to use Dijkstra algorithm. |
|
1047 |
/// It uses the functions and features of the plain \ref Dijkstra, |
|
1048 |
/// but it is much simpler to use it. |
|
1049 |
/// |
|
1050 |
/// Simplicity means that the way to change the types defined |
|
1051 |
/// in the traits class is based on functions that returns the new class |
|
1052 |
/// and not on templatable built-in classes. |
|
1053 |
/// When using the plain \ref Dijkstra |
|
1054 |
/// the new class with the modified type comes from |
|
1055 |
/// the original class by using the :: |
|
1056 |
/// operator. In the case of \ref DijkstraWizard only |
|
1057 |
/// a function have to be called and it will |
|
1058 |
/// return the needed class. |
|
1059 |
/// |
|
1060 |
/// It does not have own \ref run method. When its \ref run method is called |
|
1061 |
/// it initiates a plain \ref Dijkstra class, and calls the \ref |
|
1062 |
/// Dijkstra::run method of it. |
|
1063 |
template<class TR> |
|
1064 |
class DijkstraWizard : public TR |
|
1065 |
{ |
|
1066 |
typedef TR Base; |
|
1067 |
|
|
1068 |
///The type of the underlying digraph. |
|
1069 |
typedef typename TR::Digraph Digraph; |
|
1070 |
//\e |
|
1071 |
typedef typename Digraph::Node Node; |
|
1072 |
//\e |
|
1073 |
typedef typename Digraph::NodeIt NodeIt; |
|
1074 |
//\e |
|
1075 |
typedef typename Digraph::Arc Arc; |
|
1076 |
//\e |
|
1077 |
typedef typename Digraph::OutArcIt OutArcIt; |
|
1078 |
|
|
1079 |
///The type of the map that stores the arc lengths. |
|
1080 |
typedef typename TR::LengthMap LengthMap; |
|
1081 |
///The type of the length of the arcs. |
|
1082 |
typedef typename LengthMap::Value Value; |
|
1083 |
///\brief The type of the map that stores the last |
|
1084 |
///arcs of the shortest paths. |
|
1085 |
typedef typename TR::PredMap PredMap; |
|
1086 |
///The type of the map that stores the dists of the nodes. |
|
1087 |
typedef typename TR::DistMap DistMap; |
|
1088 |
///The heap type used by the dijkstra algorithm. |
|
1089 |
typedef typename TR::Heap Heap; |
|
1090 |
public: |
|
1091 |
/// Constructor. |
|
1092 |
DijkstraWizard() : TR() {} |
|
1093 |
|
|
1094 |
/// Constructor that requires parameters. |
|
1095 |
|
|
1096 |
/// Constructor that requires parameters. |
|
1097 |
/// These parameters will be the default values for the traits class. |
|
1098 |
DijkstraWizard(const Digraph &g,const LengthMap &l, Node s=INVALID) : |
|
1099 |
TR(g,l,s) {} |
|
1100 |
|
|
1101 |
///Copy constructor |
|
1102 |
DijkstraWizard(const TR &b) : TR(b) {} |
|
1103 |
|
|
1104 |
~DijkstraWizard() {} |
|
1105 |
|
|
1106 |
///Runs Dijkstra algorithm from a given node. |
|
1107 |
|
|
1108 |
///Runs Dijkstra algorithm from a given node. |
|
1109 |
///The node can be given by the \ref source function. |
|
1110 |
void run() |
|
1111 |
{ |
|
1112 |
if(Base::_source==INVALID) throw UninitializedParameter(); |
|
1113 |
Dijkstra<Digraph,LengthMap,TR> |
|
1114 |
dij(*reinterpret_cast<const Digraph*>(Base::_g), |
|
1115 |
*reinterpret_cast<const LengthMap*>(Base::_length)); |
|
1116 |
if(Base::_pred) dij.predMap(*reinterpret_cast<PredMap*>(Base::_pred)); |
|
1117 |
if(Base::_dist) dij.distMap(*reinterpret_cast<DistMap*>(Base::_dist)); |
|
1118 |
dij.run(Base::_source); |
|
1119 |
} |
|
1120 |
|
|
1121 |
///Runs Dijkstra algorithm from the given node. |
|
1122 |
|
|
1123 |
///Runs Dijkstra algorithm from the given node. |
|
1124 |
///\param s is the given source. |
|
1125 |
void run(Node s) |
|
1126 |
{ |
|
1127 |
Base::_source=s; |
|
1128 |
run(); |
|
1129 |
} |
|
1130 |
|
|
1131 |
template<class T> |
|
1132 |
struct DefPredMapBase : public Base { |
|
1133 |
typedef T PredMap; |
|
1134 |
static PredMap *createPredMap(const Digraph &) { return 0; }; |
|
1135 |
DefPredMapBase(const TR &b) : TR(b) {} |
|
1136 |
}; |
|
1137 |
|
|
1138 |
///\brief \ref named-templ-param "Named parameter" |
|
1139 |
///function for setting PredMap type |
|
1140 |
/// |
|
1141 |
/// \ref named-templ-param "Named parameter" |
|
1142 |
///function for setting PredMap type |
|
1143 |
/// |
|
1144 |
template<class T> |
|
1145 |
DijkstraWizard<DefPredMapBase<T> > predMap(const T &t) |
|
1146 |
{ |
|
1147 |
Base::_pred=reinterpret_cast<void*>(const_cast<T*>(&t)); |
|
1148 |
return DijkstraWizard<DefPredMapBase<T> >(*this); |
|
1149 |
} |
|
1150 |
|
|
1151 |
template<class T> |
|
1152 |
struct DefDistMapBase : public Base { |
|
1153 |
typedef T DistMap; |
|
1154 |
static DistMap *createDistMap(const Digraph &) { return 0; }; |
|
1155 |
DefDistMapBase(const TR &b) : TR(b) {} |
|
1156 |
}; |
|
1157 |
|
|
1158 |
///\brief \ref named-templ-param "Named parameter" |
|
1159 |
///function for setting DistMap type |
|
1160 |
/// |
|
1161 |
/// \ref named-templ-param "Named parameter" |
|
1162 |
///function for setting DistMap type |
|
1163 |
/// |
|
1164 |
template<class T> |
|
1165 |
DijkstraWizard<DefDistMapBase<T> > distMap(const T &t) |
|
1166 |
{ |
|
1167 |
Base::_dist=reinterpret_cast<void*>(const_cast<T*>(&t)); |
|
1168 |
return DijkstraWizard<DefDistMapBase<T> >(*this); |
|
1169 |
} |
|
1170 |
|
|
1171 |
/// Sets the source node, from which the Dijkstra algorithm runs. |
|
1172 |
|
|
1173 |
/// Sets the source node, from which the Dijkstra algorithm runs. |
|
1174 |
/// \param s is the source node. |
|
1175 |
DijkstraWizard<TR> &source(Node s) |
|
1176 |
{ |
|
1177 |
Base::_source=s; |
|
1178 |
return *this; |
|
1179 |
} |
|
1180 |
|
|
1181 |
}; |
|
1182 |
|
|
1183 |
///Function type interface for Dijkstra algorithm. |
|
1184 |
|
|
1185 |
/// \ingroup shortest_path |
|
1186 |
///Function type interface for Dijkstra algorithm. |
|
1187 |
/// |
|
1188 |
///This function also has several |
|
1189 |
///\ref named-templ-func-param "named parameters", |
|
1190 |
///they are declared as the members of class \ref DijkstraWizard. |
|
1191 |
///The following |
|
1192 |
///example shows how to use these parameters. |
|
1193 |
///\code |
|
1194 |
/// dijkstra(g,length,source).predMap(preds).run(); |
|
1195 |
///\endcode |
|
1196 |
///\warning Don't forget to put the \ref DijkstraWizard::run() "run()" |
|
1197 |
///to the end of the parameter list. |
|
1198 |
///\sa DijkstraWizard |
|
1199 |
///\sa Dijkstra |
|
1200 |
template<class GR, class LM> |
|
1201 |
DijkstraWizard<DijkstraWizardBase<GR,LM> > |
|
1202 |
dijkstra(const GR &g,const LM &l,typename GR::Node s=INVALID) |
|
1203 |
{ |
|
1204 |
return DijkstraWizard<DijkstraWizardBase<GR,LM> >(g,l,s); |
|
1205 |
} |
|
1206 |
|
|
1207 |
} //END OF NAMESPACE LEMON |
|
1208 |
|
|
1209 |
#endif |
... | ... |
@@ -17,5 +17,9 @@ |
17 | 17 |
lemon_HEADERS += \ |
18 |
lemon/ |
|
18 |
lemon/bfs.h \ |
|
19 |
lemon/bin_heap.h \ |
|
20 |
lemon/dfs.h \ |
|
21 |
lemon/dijkstra.h \ |
|
19 | 22 |
lemon/dim2.h \ |
20 | 23 |
lemon/error.h \ |
24 |
lemon/graph_utils.h \ |
|
21 | 25 |
lemon/list_graph.h \ |
... | ... |
@@ -34,2 +38,3 @@ |
34 | 38 |
lemon/bits/map_extender.h \ |
39 |
lemon/bits/path_dump.h \ |
|
35 | 40 |
lemon/bits/traits.h \ |
... | ... |
@@ -42,2 +47,3 @@ |
42 | 47 |
lemon/concepts/graph.h \ |
48 |
lemon/concepts/heap.h \ |
|
43 | 49 |
lemon/concepts/maps.h \ |
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