[906] | 1 | /* -*- C++ -*- |
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| 2 | * |
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[1956] | 3 | * This file is a part of LEMON, a generic C++ optimization library |
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| 4 | * |
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| 5 | * Copyright (C) 2003-2006 |
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| 6 | * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
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[1359] | 7 | * (Egervary Research Group on Combinatorial Optimization, EGRES). |
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[906] | 8 | * |
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| 9 | * Permission to use, modify and distribute this software is granted |
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| 10 | * provided that this copyright notice appears in all copies. For |
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| 11 | * precise terms see the accompanying LICENSE file. |
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| 12 | * |
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| 13 | * This software is provided "AS IS" with no warranty of any kind, |
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| 14 | * express or implied, and with no claim as to its suitability for any |
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| 15 | * purpose. |
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| 16 | * |
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| 17 | */ |
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| 18 | |
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[921] | 19 | #ifndef LEMON_BFS_H |
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| 20 | #define LEMON_BFS_H |
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[774] | 21 | |
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| 22 | ///\ingroup flowalgs |
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| 23 | ///\file |
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| 24 | ///\brief Bfs algorithm. |
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| 25 | |
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[1218] | 26 | #include <lemon/list_graph.h> |
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| 27 | #include <lemon/graph_utils.h> |
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[1993] | 28 | #include <lemon/bits/invalid.h> |
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[1218] | 29 | #include <lemon/error.h> |
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| 30 | #include <lemon/maps.h> |
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[774] | 31 | |
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[921] | 32 | namespace lemon { |
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[774] | 33 | |
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| 34 | |
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[1218] | 35 | |
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| 36 | ///Default traits class of Bfs class. |
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| 37 | |
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| 38 | ///Default traits class of Bfs class. |
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| 39 | ///\param GR Graph type. |
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| 40 | template<class GR> |
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| 41 | struct BfsDefaultTraits |
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| 42 | { |
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| 43 | ///The graph type the algorithm runs on. |
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| 44 | typedef GR Graph; |
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| 45 | ///\brief The type of the map that stores the last |
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| 46 | ///edges of the shortest paths. |
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| 47 | /// |
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| 48 | ///The type of the map that stores the last |
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| 49 | ///edges of the shortest paths. |
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[2260] | 50 | ///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
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[1218] | 51 | /// |
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| 52 | typedef typename Graph::template NodeMap<typename GR::Edge> PredMap; |
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| 53 | ///Instantiates a PredMap. |
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| 54 | |
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| 55 | ///This function instantiates a \ref PredMap. |
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| 56 | ///\param G is the graph, to which we would like to define the PredMap. |
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| 57 | ///\todo The graph alone may be insufficient to initialize |
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| 58 | static PredMap *createPredMap(const GR &G) |
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| 59 | { |
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| 60 | return new PredMap(G); |
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| 61 | } |
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| 62 | ///The type of the map that indicates which nodes are processed. |
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| 63 | |
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| 64 | ///The type of the map that indicates which nodes are processed. |
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[2260] | 65 | ///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
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[1218] | 66 | ///\todo named parameter to set this type, function to read and write. |
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| 67 | typedef NullMap<typename Graph::Node,bool> ProcessedMap; |
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| 68 | ///Instantiates a ProcessedMap. |
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| 69 | |
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| 70 | ///This function instantiates a \ref ProcessedMap. |
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[1536] | 71 | ///\param g is the graph, to which |
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[1218] | 72 | ///we would like to define the \ref ProcessedMap |
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[1536] | 73 | #ifdef DOXYGEN |
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| 74 | static ProcessedMap *createProcessedMap(const GR &g) |
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| 75 | #else |
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[1367] | 76 | static ProcessedMap *createProcessedMap(const GR &) |
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[1536] | 77 | #endif |
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[1218] | 78 | { |
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| 79 | return new ProcessedMap(); |
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| 80 | } |
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| 81 | ///The type of the map that indicates which nodes are reached. |
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| 82 | |
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| 83 | ///The type of the map that indicates which nodes are reached. |
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[2260] | 84 | ///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
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[1218] | 85 | ///\todo named parameter to set this type, function to read and write. |
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| 86 | typedef typename Graph::template NodeMap<bool> ReachedMap; |
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| 87 | ///Instantiates a ReachedMap. |
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| 88 | |
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| 89 | ///This function instantiates a \ref ReachedMap. |
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| 90 | ///\param G is the graph, to which |
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| 91 | ///we would like to define the \ref ReachedMap. |
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| 92 | static ReachedMap *createReachedMap(const GR &G) |
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| 93 | { |
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| 94 | return new ReachedMap(G); |
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| 95 | } |
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| 96 | ///The type of the map that stores the dists of the nodes. |
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| 97 | |
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| 98 | ///The type of the map that stores the dists of the nodes. |
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[2260] | 99 | ///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
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[1218] | 100 | /// |
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| 101 | typedef typename Graph::template NodeMap<int> DistMap; |
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| 102 | ///Instantiates a DistMap. |
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| 103 | |
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| 104 | ///This function instantiates a \ref DistMap. |
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| 105 | ///\param G is the graph, to which we would like to define the \ref DistMap |
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| 106 | static DistMap *createDistMap(const GR &G) |
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| 107 | { |
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| 108 | return new DistMap(G); |
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| 109 | } |
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| 110 | }; |
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| 111 | |
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[781] | 112 | ///%BFS algorithm class. |
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[1218] | 113 | |
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| 114 | ///\ingroup flowalgs |
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| 115 | ///This class provides an efficient implementation of the %BFS algorithm. |
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[774] | 116 | /// |
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[1218] | 117 | ///\param GR The graph type the algorithm runs on. The default value is |
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| 118 | ///\ref ListGraph. The value of GR is not used directly by Bfs, it |
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| 119 | ///is only passed to \ref BfsDefaultTraits. |
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| 120 | ///\param TR Traits class to set various data types used by the algorithm. |
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| 121 | ///The default traits class is |
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| 122 | ///\ref BfsDefaultTraits "BfsDefaultTraits<GR>". |
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| 123 | ///See \ref BfsDefaultTraits for the documentation of |
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| 124 | ///a Bfs traits class. |
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| 125 | /// |
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[1270] | 126 | ///\author Alpar Juttner |
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[774] | 127 | |
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| 128 | #ifdef DOXYGEN |
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[1218] | 129 | template <typename GR, |
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| 130 | typename TR> |
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[774] | 131 | #else |
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[1218] | 132 | template <typename GR=ListGraph, |
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| 133 | typename TR=BfsDefaultTraits<GR> > |
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[774] | 134 | #endif |
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[1218] | 135 | class Bfs { |
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[774] | 136 | public: |
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[1218] | 137 | /** |
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| 138 | * \brief \ref Exception for uninitialized parameters. |
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| 139 | * |
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| 140 | * This error represents problems in the initialization |
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| 141 | * of the parameters of the algorithms. |
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| 142 | */ |
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| 143 | class UninitializedParameter : public lemon::UninitializedParameter { |
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| 144 | public: |
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[2151] | 145 | virtual const char* what() const throw() { |
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[1218] | 146 | return "lemon::Bfs::UninitializedParameter"; |
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| 147 | } |
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| 148 | }; |
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| 149 | |
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| 150 | typedef TR Traits; |
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[774] | 151 | ///The type of the underlying graph. |
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[1218] | 152 | typedef typename TR::Graph Graph; |
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[911] | 153 | ///\e |
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[774] | 154 | typedef typename Graph::Node Node; |
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[911] | 155 | ///\e |
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[774] | 156 | typedef typename Graph::NodeIt NodeIt; |
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[911] | 157 | ///\e |
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[774] | 158 | typedef typename Graph::Edge Edge; |
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[911] | 159 | ///\e |
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[774] | 160 | typedef typename Graph::OutEdgeIt OutEdgeIt; |
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| 161 | |
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| 162 | ///\brief The type of the map that stores the last |
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| 163 | ///edges of the shortest paths. |
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[1218] | 164 | typedef typename TR::PredMap PredMap; |
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| 165 | ///The type of the map indicating which nodes are reached. |
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| 166 | typedef typename TR::ReachedMap ReachedMap; |
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| 167 | ///The type of the map indicating which nodes are processed. |
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| 168 | typedef typename TR::ProcessedMap ProcessedMap; |
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[774] | 169 | ///The type of the map that stores the dists of the nodes. |
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[1218] | 170 | typedef typename TR::DistMap DistMap; |
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[774] | 171 | private: |
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[802] | 172 | /// Pointer to the underlying graph. |
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[774] | 173 | const Graph *G; |
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[802] | 174 | ///Pointer to the map of predecessors edges. |
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[1218] | 175 | PredMap *_pred; |
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| 176 | ///Indicates if \ref _pred is locally allocated (\c true) or not. |
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| 177 | bool local_pred; |
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[802] | 178 | ///Pointer to the map of distances. |
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[1218] | 179 | DistMap *_dist; |
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| 180 | ///Indicates if \ref _dist is locally allocated (\c true) or not. |
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| 181 | bool local_dist; |
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| 182 | ///Pointer to the map of reached status of the nodes. |
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| 183 | ReachedMap *_reached; |
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| 184 | ///Indicates if \ref _reached is locally allocated (\c true) or not. |
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| 185 | bool local_reached; |
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| 186 | ///Pointer to the map of processed status of the nodes. |
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| 187 | ProcessedMap *_processed; |
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| 188 | ///Indicates if \ref _processed is locally allocated (\c true) or not. |
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| 189 | bool local_processed; |
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[774] | 190 | |
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[1218] | 191 | std::vector<typename Graph::Node> _queue; |
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| 192 | int _queue_head,_queue_tail,_queue_next_dist; |
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| 193 | int _curr_dist; |
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[774] | 194 | |
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[1218] | 195 | ///Creates the maps if necessary. |
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| 196 | |
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| 197 | ///\todo Better memory allocation (instead of new). |
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| 198 | void create_maps() |
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[774] | 199 | { |
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[1218] | 200 | if(!_pred) { |
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| 201 | local_pred = true; |
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| 202 | _pred = Traits::createPredMap(*G); |
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[774] | 203 | } |
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[1218] | 204 | if(!_dist) { |
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| 205 | local_dist = true; |
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| 206 | _dist = Traits::createDistMap(*G); |
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[774] | 207 | } |
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[1218] | 208 | if(!_reached) { |
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| 209 | local_reached = true; |
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| 210 | _reached = Traits::createReachedMap(*G); |
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| 211 | } |
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| 212 | if(!_processed) { |
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| 213 | local_processed = true; |
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| 214 | _processed = Traits::createProcessedMap(*G); |
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[774] | 215 | } |
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| 216 | } |
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[1710] | 217 | |
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| 218 | protected: |
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[774] | 219 | |
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[1710] | 220 | Bfs() {} |
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| 221 | |
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| 222 | public: |
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[1218] | 223 | |
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[1710] | 224 | typedef Bfs Create; |
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| 225 | |
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[1218] | 226 | ///\name Named template parameters |
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| 227 | |
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| 228 | ///@{ |
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| 229 | |
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| 230 | template <class T> |
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| 231 | struct DefPredMapTraits : public Traits { |
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| 232 | typedef T PredMap; |
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[1799] | 233 | static PredMap *createPredMap(const Graph &) |
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[1218] | 234 | { |
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| 235 | throw UninitializedParameter(); |
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| 236 | } |
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| 237 | }; |
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| 238 | ///\ref named-templ-param "Named parameter" for setting PredMap type |
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| 239 | |
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| 240 | ///\ref named-templ-param "Named parameter" for setting PredMap type |
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| 241 | /// |
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| 242 | template <class T> |
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[1709] | 243 | struct DefPredMap : public Bfs< Graph, DefPredMapTraits<T> > { |
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| 244 | typedef Bfs< Graph, DefPredMapTraits<T> > Create; |
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| 245 | }; |
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[1218] | 246 | |
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| 247 | template <class T> |
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| 248 | struct DefDistMapTraits : public Traits { |
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| 249 | typedef T DistMap; |
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[1799] | 250 | static DistMap *createDistMap(const Graph &) |
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[1218] | 251 | { |
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| 252 | throw UninitializedParameter(); |
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| 253 | } |
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| 254 | }; |
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| 255 | ///\ref named-templ-param "Named parameter" for setting DistMap type |
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| 256 | |
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| 257 | ///\ref named-templ-param "Named parameter" for setting DistMap type |
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| 258 | /// |
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| 259 | template <class T> |
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[1709] | 260 | struct DefDistMap : public Bfs< Graph, DefDistMapTraits<T> > { |
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| 261 | typedef Bfs< Graph, DefDistMapTraits<T> > Create; |
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| 262 | }; |
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[1218] | 263 | |
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| 264 | template <class T> |
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| 265 | struct DefReachedMapTraits : public Traits { |
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| 266 | typedef T ReachedMap; |
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[1799] | 267 | static ReachedMap *createReachedMap(const Graph &) |
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[1218] | 268 | { |
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| 269 | throw UninitializedParameter(); |
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| 270 | } |
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| 271 | }; |
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| 272 | ///\ref named-templ-param "Named parameter" for setting ReachedMap type |
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| 273 | |
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| 274 | ///\ref named-templ-param "Named parameter" for setting ReachedMap type |
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| 275 | /// |
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| 276 | template <class T> |
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[1709] | 277 | struct DefReachedMap : public Bfs< Graph, DefReachedMapTraits<T> > { |
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| 278 | typedef Bfs< Graph, DefReachedMapTraits<T> > Create; |
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| 279 | }; |
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[1218] | 280 | |
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| 281 | template <class T> |
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| 282 | struct DefProcessedMapTraits : public Traits { |
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| 283 | typedef T ProcessedMap; |
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[2033] | 284 | static ProcessedMap *createProcessedMap(const Graph &) |
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[1218] | 285 | { |
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| 286 | throw UninitializedParameter(); |
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| 287 | } |
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| 288 | }; |
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| 289 | ///\ref named-templ-param "Named parameter" for setting ProcessedMap type |
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| 290 | |
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| 291 | ///\ref named-templ-param "Named parameter" for setting ProcessedMap type |
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| 292 | /// |
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| 293 | template <class T> |
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[1709] | 294 | struct DefProcessedMap : public Bfs< Graph, DefProcessedMapTraits<T> > { |
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| 295 | typedef Bfs< Graph, DefProcessedMapTraits<T> > Create; |
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| 296 | }; |
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[1218] | 297 | |
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| 298 | struct DefGraphProcessedMapTraits : public Traits { |
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| 299 | typedef typename Graph::template NodeMap<bool> ProcessedMap; |
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| 300 | static ProcessedMap *createProcessedMap(const Graph &G) |
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| 301 | { |
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| 302 | return new ProcessedMap(G); |
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| 303 | } |
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| 304 | }; |
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| 305 | ///\brief \ref named-templ-param "Named parameter" |
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| 306 | ///for setting the ProcessedMap type to be Graph::NodeMap<bool>. |
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| 307 | /// |
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| 308 | ///\ref named-templ-param "Named parameter" |
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| 309 | ///for setting the ProcessedMap type to be Graph::NodeMap<bool>. |
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[1270] | 310 | ///If you don't set it explicitly, it will be automatically allocated. |
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[1218] | 311 | template <class T> |
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[1709] | 312 | struct DefProcessedMapToBeDefaultMap : |
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| 313 | public Bfs< Graph, DefGraphProcessedMapTraits> { |
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| 314 | typedef Bfs< Graph, DefGraphProcessedMapTraits> Create; |
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| 315 | }; |
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[1218] | 316 | |
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| 317 | ///@} |
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| 318 | |
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| 319 | public: |
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| 320 | |
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[802] | 321 | ///Constructor. |
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| 322 | |
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| 323 | ///\param _G the graph the algorithm will run on. |
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[911] | 324 | /// |
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[774] | 325 | Bfs(const Graph& _G) : |
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| 326 | G(&_G), |
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[1218] | 327 | _pred(NULL), local_pred(false), |
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| 328 | _dist(NULL), local_dist(false), |
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| 329 | _reached(NULL), local_reached(false), |
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| 330 | _processed(NULL), local_processed(false) |
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[774] | 331 | { } |
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| 332 | |
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[802] | 333 | ///Destructor. |
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[774] | 334 | ~Bfs() |
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| 335 | { |
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[1218] | 336 | if(local_pred) delete _pred; |
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| 337 | if(local_dist) delete _dist; |
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| 338 | if(local_reached) delete _reached; |
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| 339 | if(local_processed) delete _processed; |
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[774] | 340 | } |
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| 341 | |
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| 342 | ///Sets the map storing the predecessor edges. |
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| 343 | |
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| 344 | ///Sets the map storing the predecessor edges. |
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| 345 | ///If you don't use this function before calling \ref run(), |
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[1270] | 346 | ///it will allocate one. The destructor deallocates this |
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[774] | 347 | ///automatically allocated map, of course. |
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| 348 | ///\return <tt> (*this) </tt> |
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[1218] | 349 | Bfs &predMap(PredMap &m) |
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[774] | 350 | { |
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[1218] | 351 | if(local_pred) { |
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| 352 | delete _pred; |
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| 353 | local_pred=false; |
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[774] | 354 | } |
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[1218] | 355 | _pred = &m; |
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[774] | 356 | return *this; |
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| 357 | } |
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| 358 | |
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[1218] | 359 | ///Sets the map indicating the reached nodes. |
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[774] | 360 | |
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[1218] | 361 | ///Sets the map indicating the reached nodes. |
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[774] | 362 | ///If you don't use this function before calling \ref run(), |
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[1270] | 363 | ///it will allocate one. The destructor deallocates this |
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[774] | 364 | ///automatically allocated map, of course. |
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| 365 | ///\return <tt> (*this) </tt> |
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[1218] | 366 | Bfs &reachedMap(ReachedMap &m) |
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[774] | 367 | { |
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[1218] | 368 | if(local_reached) { |
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| 369 | delete _reached; |
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| 370 | local_reached=false; |
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[774] | 371 | } |
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[1218] | 372 | _reached = &m; |
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[774] | 373 | return *this; |
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| 374 | } |
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| 375 | |
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[1218] | 376 | ///Sets the map indicating the processed nodes. |
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| 377 | |
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| 378 | ///Sets the map indicating the processed nodes. |
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| 379 | ///If you don't use this function before calling \ref run(), |
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[1270] | 380 | ///it will allocate one. The destructor deallocates this |
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[1218] | 381 | ///automatically allocated map, of course. |
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| 382 | ///\return <tt> (*this) </tt> |
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| 383 | Bfs &processedMap(ProcessedMap &m) |
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| 384 | { |
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| 385 | if(local_processed) { |
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| 386 | delete _processed; |
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| 387 | local_processed=false; |
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| 388 | } |
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| 389 | _processed = &m; |
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| 390 | return *this; |
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| 391 | } |
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| 392 | |
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[774] | 393 | ///Sets the map storing the distances calculated by the algorithm. |
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| 394 | |
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| 395 | ///Sets the map storing the distances calculated by the algorithm. |
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| 396 | ///If you don't use this function before calling \ref run(), |
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[1270] | 397 | ///it will allocate one. The destructor deallocates this |
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[774] | 398 | ///automatically allocated map, of course. |
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| 399 | ///\return <tt> (*this) </tt> |
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[1218] | 400 | Bfs &distMap(DistMap &m) |
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[774] | 401 | { |
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[1218] | 402 | if(local_dist) { |
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| 403 | delete _dist; |
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| 404 | local_dist=false; |
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[774] | 405 | } |
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[1218] | 406 | _dist = &m; |
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[774] | 407 | return *this; |
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| 408 | } |
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| 409 | |
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[1218] | 410 | public: |
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| 411 | ///\name Execution control |
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| 412 | ///The simplest way to execute the algorithm is to use |
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| 413 | ///one of the member functions called \c run(...). |
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| 414 | ///\n |
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| 415 | ///If you need more control on the execution, |
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| 416 | ///first you must call \ref init(), then you can add several source nodes |
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| 417 | ///with \ref addSource(). |
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| 418 | ///Finally \ref start() will perform the actual path |
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| 419 | ///computation. |
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| 420 | |
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| 421 | ///@{ |
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| 422 | |
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| 423 | ///Initializes the internal data structures. |
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| 424 | |
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| 425 | ///Initializes the internal data structures. |
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| 426 | /// |
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| 427 | void init() |
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| 428 | { |
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| 429 | create_maps(); |
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| 430 | _queue.resize(countNodes(*G)); |
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| 431 | _queue_head=_queue_tail=0; |
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| 432 | _curr_dist=1; |
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[774] | 433 | for ( NodeIt u(*G) ; u!=INVALID ; ++u ) { |
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[1218] | 434 | _pred->set(u,INVALID); |
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| 435 | _reached->set(u,false); |
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| 436 | _processed->set(u,false); |
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[774] | 437 | } |
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| 438 | } |
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| 439 | |
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[1218] | 440 | ///Adds a new source node. |
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[774] | 441 | |
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[1218] | 442 | ///Adds a new source node to the set of nodes to be processed. |
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| 443 | /// |
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| 444 | void addSource(Node s) |
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| 445 | { |
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| 446 | if(!(*_reached)[s]) |
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| 447 | { |
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| 448 | _reached->set(s,true); |
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| 449 | _pred->set(s,INVALID); |
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| 450 | _dist->set(s,0); |
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| 451 | _queue[_queue_head++]=s; |
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| 452 | _queue_next_dist=_queue_head; |
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| 453 | } |
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| 454 | } |
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| 455 | |
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| 456 | ///Processes the next node. |
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| 457 | |
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| 458 | ///Processes the next node. |
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| 459 | /// |
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[1516] | 460 | ///\return The processed node. |
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| 461 | /// |
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[1218] | 462 | ///\warning The queue must not be empty! |
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[1516] | 463 | Node processNextNode() |
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[1218] | 464 | { |
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| 465 | if(_queue_tail==_queue_next_dist) { |
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| 466 | _curr_dist++; |
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| 467 | _queue_next_dist=_queue_head; |
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| 468 | } |
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| 469 | Node n=_queue[_queue_tail++]; |
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| 470 | _processed->set(n,true); |
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| 471 | Node m; |
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| 472 | for(OutEdgeIt e(*G,n);e!=INVALID;++e) |
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| 473 | if(!(*_reached)[m=G->target(e)]) { |
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| 474 | _queue[_queue_head++]=m; |
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| 475 | _reached->set(m,true); |
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| 476 | _pred->set(m,e); |
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| 477 | _dist->set(m,_curr_dist); |
---|
| 478 | } |
---|
[1516] | 479 | return n; |
---|
[1218] | 480 | } |
---|
[2300] | 481 | |
---|
| 482 | ///Processes the next node. |
---|
| 483 | |
---|
| 484 | ///Processes the next node. And checks that the given target node |
---|
| 485 | ///is reached. If the target node is reachable from the processed |
---|
| 486 | ///node then the reached parameter will be set true. The reached |
---|
| 487 | ///parameter should be initially false. |
---|
| 488 | /// |
---|
| 489 | ///\param target The target node. |
---|
| 490 | ///\retval reached Indicates that the target node is reached. |
---|
| 491 | ///\return The processed node. |
---|
| 492 | /// |
---|
| 493 | ///\warning The queue must not be empty! |
---|
| 494 | Node processNextNode(Node target, bool& reached) |
---|
| 495 | { |
---|
| 496 | if(_queue_tail==_queue_next_dist) { |
---|
| 497 | _curr_dist++; |
---|
| 498 | _queue_next_dist=_queue_head; |
---|
| 499 | } |
---|
| 500 | Node n=_queue[_queue_tail++]; |
---|
| 501 | _processed->set(n,true); |
---|
| 502 | Node m; |
---|
| 503 | for(OutEdgeIt e(*G,n);e!=INVALID;++e) |
---|
| 504 | if(!(*_reached)[m=G->target(e)]) { |
---|
| 505 | _queue[_queue_head++]=m; |
---|
| 506 | _reached->set(m,true); |
---|
| 507 | _pred->set(m,e); |
---|
| 508 | _dist->set(m,_curr_dist); |
---|
| 509 | reached = reached || (target == m); |
---|
| 510 | } |
---|
| 511 | return n; |
---|
| 512 | } |
---|
| 513 | |
---|
| 514 | ///Processes the next node. |
---|
| 515 | |
---|
| 516 | ///Processes the next node. And checks that at least one of |
---|
| 517 | ///reached node has true value in the \c nm nodemap. If one node |
---|
| 518 | ///with true value is reachable from the processed node then the |
---|
| 519 | ///reached parameter will be set true. The reached parameter |
---|
| 520 | ///should be initially false. |
---|
| 521 | /// |
---|
| 522 | ///\param target The nodemaps of possible targets. |
---|
| 523 | ///\retval reached Indicates that one of the target nodes is reached. |
---|
| 524 | ///\return The processed node. |
---|
| 525 | /// |
---|
| 526 | ///\warning The queue must not be empty! |
---|
| 527 | template<class NM> |
---|
| 528 | Node processNextNode(const NM& nm, bool& reached) |
---|
| 529 | { |
---|
| 530 | if(_queue_tail==_queue_next_dist) { |
---|
| 531 | _curr_dist++; |
---|
| 532 | _queue_next_dist=_queue_head; |
---|
| 533 | } |
---|
| 534 | Node n=_queue[_queue_tail++]; |
---|
| 535 | _processed->set(n,true); |
---|
| 536 | Node m; |
---|
| 537 | for(OutEdgeIt e(*G,n);e!=INVALID;++e) |
---|
| 538 | if(!(*_reached)[m=G->target(e)]) { |
---|
| 539 | _queue[_queue_head++]=m; |
---|
| 540 | _reached->set(m,true); |
---|
| 541 | _pred->set(m,e); |
---|
| 542 | _dist->set(m,_curr_dist); |
---|
| 543 | reached = reached || nm[m]; |
---|
| 544 | } |
---|
| 545 | return n; |
---|
| 546 | } |
---|
[1218] | 547 | |
---|
[1665] | 548 | ///Next node to be processed. |
---|
| 549 | |
---|
| 550 | ///Next node to be processed. |
---|
| 551 | /// |
---|
| 552 | ///\return The next node to be processed or INVALID if the queue is |
---|
| 553 | /// empty. |
---|
[1694] | 554 | Node nextNode() |
---|
[1665] | 555 | { |
---|
| 556 | return _queue_tail<_queue_head?_queue[_queue_tail]:INVALID; |
---|
| 557 | } |
---|
| 558 | |
---|
[1218] | 559 | ///\brief Returns \c false if there are nodes |
---|
| 560 | ///to be processed in the queue |
---|
| 561 | /// |
---|
| 562 | ///Returns \c false if there are nodes |
---|
| 563 | ///to be processed in the queue |
---|
| 564 | bool emptyQueue() { return _queue_tail==_queue_head; } |
---|
| 565 | ///Returns the number of the nodes to be processed. |
---|
| 566 | |
---|
| 567 | ///Returns the number of the nodes to be processed in the queue. |
---|
| 568 | /// |
---|
| 569 | int queueSize() { return _queue_head-_queue_tail; } |
---|
| 570 | |
---|
| 571 | ///Executes the algorithm. |
---|
| 572 | |
---|
| 573 | ///Executes the algorithm. |
---|
| 574 | /// |
---|
| 575 | ///\pre init() must be called and at least one node should be added |
---|
| 576 | ///with addSource() before using this function. |
---|
| 577 | /// |
---|
| 578 | ///This method runs the %BFS algorithm from the root node(s) |
---|
| 579 | ///in order to |
---|
| 580 | ///compute the |
---|
| 581 | ///shortest path to each node. The algorithm computes |
---|
| 582 | ///- The shortest path tree. |
---|
| 583 | ///- The distance of each node from the root(s). |
---|
| 584 | /// |
---|
| 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 |
---|
| 599 | ///compute the |
---|
| 600 | ///shortest path to \c dest. The algorithm computes |
---|
| 601 | ///- The shortest path to \c dest. |
---|
| 602 | ///- The distance of \c dest from the root(s). |
---|
| 603 | /// |
---|
| 604 | void start(Node dest) |
---|
| 605 | { |
---|
[2300] | 606 | bool reached = false; |
---|
| 607 | while ( !emptyQueue() && !reached) processNextNode(dest, reached); |
---|
[1218] | 608 | } |
---|
| 609 | |
---|
| 610 | ///Executes the algorithm until a condition is met. |
---|
| 611 | |
---|
| 612 | ///Executes the algorithm until a condition is met. |
---|
| 613 | /// |
---|
| 614 | ///\pre init() must be called and at least one node should be added |
---|
| 615 | ///with addSource() before using this function. |
---|
| 616 | /// |
---|
| 617 | ///\param nm must be a bool (or convertible) node map. The algorithm |
---|
| 618 | ///will stop when it reaches a node \c v with <tt>nm[v]==true</tt>. |
---|
[2300] | 619 | ///\todo query the reached target |
---|
[1218] | 620 | template<class NM> |
---|
[1755] | 621 | void start(const NM &nm) |
---|
| 622 | { |
---|
[2300] | 623 | bool reached = false; |
---|
| 624 | while ( !emptyQueue() && !reached) processNextNode(nm, reached); |
---|
[1755] | 625 | } |
---|
[1218] | 626 | |
---|
| 627 | ///Runs %BFS algorithm from node \c s. |
---|
| 628 | |
---|
| 629 | ///This method runs the %BFS algorithm from a root node \c s |
---|
| 630 | ///in order to |
---|
| 631 | ///compute the |
---|
| 632 | ///shortest path to each node. The algorithm computes |
---|
| 633 | ///- The shortest path tree. |
---|
| 634 | ///- The distance of each node from the root. |
---|
| 635 | /// |
---|
| 636 | ///\note d.run(s) is just a shortcut of the following code. |
---|
| 637 | ///\code |
---|
| 638 | /// d.init(); |
---|
| 639 | /// d.addSource(s); |
---|
| 640 | /// d.start(); |
---|
| 641 | ///\endcode |
---|
| 642 | void run(Node s) { |
---|
| 643 | init(); |
---|
| 644 | addSource(s); |
---|
| 645 | start(); |
---|
| 646 | } |
---|
| 647 | |
---|
| 648 | ///Finds the shortest path between \c s and \c t. |
---|
| 649 | |
---|
| 650 | ///Finds the shortest path between \c s and \c t. |
---|
| 651 | /// |
---|
| 652 | ///\return The length of the shortest s---t path if there exists one, |
---|
| 653 | ///0 otherwise. |
---|
| 654 | ///\note Apart from the return value, d.run(s) is |
---|
| 655 | ///just a shortcut of the following code. |
---|
| 656 | ///\code |
---|
| 657 | /// d.init(); |
---|
| 658 | /// d.addSource(s); |
---|
| 659 | /// d.start(t); |
---|
| 660 | ///\endcode |
---|
| 661 | int run(Node s,Node t) { |
---|
| 662 | init(); |
---|
| 663 | addSource(s); |
---|
| 664 | start(t); |
---|
[2300] | 665 | return reached(t)? _curr_dist : 0; |
---|
[1218] | 666 | } |
---|
| 667 | |
---|
| 668 | ///@} |
---|
| 669 | |
---|
| 670 | ///\name Query Functions |
---|
| 671 | ///The result of the %BFS algorithm can be obtained using these |
---|
| 672 | ///functions.\n |
---|
| 673 | ///Before the use of these functions, |
---|
| 674 | ///either run() or start() must be called. |
---|
| 675 | |
---|
| 676 | ///@{ |
---|
| 677 | |
---|
[1283] | 678 | ///Copies the shortest path to \c t into \c p |
---|
| 679 | |
---|
| 680 | ///This function copies the shortest path to \c t into \c p. |
---|
[1536] | 681 | ///If \c t is a source itself or unreachable, then it does not |
---|
[1283] | 682 | ///alter \c p. |
---|
| 683 | ///\return Returns \c true if a path to \c t was actually copied to \c p, |
---|
| 684 | ///\c false otherwise. |
---|
| 685 | ///\sa DirPath |
---|
| 686 | template<class P> |
---|
| 687 | bool getPath(P &p,Node t) |
---|
| 688 | { |
---|
| 689 | if(reached(t)) { |
---|
| 690 | p.clear(); |
---|
| 691 | typename P::Builder b(p); |
---|
[1763] | 692 | for(b.setStartNode(t);predEdge(t)!=INVALID;t=predNode(t)) |
---|
| 693 | b.pushFront(predEdge(t)); |
---|
[1283] | 694 | b.commit(); |
---|
| 695 | return true; |
---|
| 696 | } |
---|
| 697 | return false; |
---|
| 698 | } |
---|
| 699 | |
---|
[1218] | 700 | ///The distance of a node from the root(s). |
---|
| 701 | |
---|
| 702 | ///Returns the distance of a node from the root(s). |
---|
[774] | 703 | ///\pre \ref run() must be called before using this function. |
---|
[1218] | 704 | ///\warning If node \c v in unreachable from the root(s) the return value |
---|
[1270] | 705 | ///of this function is undefined. |
---|
[1218] | 706 | int dist(Node v) const { return (*_dist)[v]; } |
---|
[774] | 707 | |
---|
[1218] | 708 | ///Returns the 'previous edge' of the shortest path tree. |
---|
[774] | 709 | |
---|
[1218] | 710 | ///For a node \c v it returns the 'previous edge' |
---|
| 711 | ///of the shortest path tree, |
---|
| 712 | ///i.e. it returns the last edge of a shortest path from the root(s) to \c |
---|
[774] | 713 | ///v. It is \ref INVALID |
---|
[1218] | 714 | ///if \c v is unreachable from the root(s) or \c v is a root. The |
---|
| 715 | ///shortest path tree used here is equal to the shortest path tree used in |
---|
[1631] | 716 | ///\ref predNode(). |
---|
[1218] | 717 | ///\pre Either \ref run() or \ref start() must be called before using |
---|
[774] | 718 | ///this function. |
---|
[1763] | 719 | Edge predEdge(Node v) const { return (*_pred)[v];} |
---|
[774] | 720 | |
---|
[1218] | 721 | ///Returns the 'previous node' of the shortest path tree. |
---|
[774] | 722 | |
---|
[1218] | 723 | ///For a node \c v it returns the 'previous node' |
---|
| 724 | ///of the shortest path tree, |
---|
[774] | 725 | ///i.e. it returns the last but one node from a shortest path from the |
---|
[1218] | 726 | ///root(a) to \c /v. |
---|
| 727 | ///It is INVALID if \c v is unreachable from the root(s) or |
---|
| 728 | ///if \c v itself a root. |
---|
| 729 | ///The shortest path tree used here is equal to the shortest path |
---|
[1763] | 730 | ///tree used in \ref predEdge(). |
---|
[1218] | 731 | ///\pre Either \ref run() or \ref start() must be called before |
---|
[774] | 732 | ///using this function. |
---|
[1218] | 733 | Node predNode(Node v) const { return (*_pred)[v]==INVALID ? INVALID: |
---|
| 734 | G->source((*_pred)[v]); } |
---|
[774] | 735 | |
---|
| 736 | ///Returns a reference to the NodeMap of distances. |
---|
[1218] | 737 | |
---|
| 738 | ///Returns a reference to the NodeMap of distances. |
---|
| 739 | ///\pre Either \ref run() or \ref init() must |
---|
[774] | 740 | ///be called before using this function. |
---|
[1218] | 741 | const DistMap &distMap() const { return *_dist;} |
---|
[774] | 742 | |
---|
[1218] | 743 | ///Returns a reference to the shortest path tree map. |
---|
[774] | 744 | |
---|
| 745 | ///Returns a reference to the NodeMap of the edges of the |
---|
[1218] | 746 | ///shortest path tree. |
---|
| 747 | ///\pre Either \ref run() or \ref init() |
---|
| 748 | ///must be called before using this function. |
---|
| 749 | const PredMap &predMap() const { return *_pred;} |
---|
[774] | 750 | |
---|
| 751 | ///Checks if a node is reachable from the root. |
---|
| 752 | |
---|
| 753 | ///Returns \c true if \c v is reachable from the root. |
---|
[1270] | 754 | ///\warning The source nodes are indicated as unreached. |
---|
[1218] | 755 | ///\pre Either \ref run() or \ref start() |
---|
| 756 | ///must be called before using this function. |
---|
[774] | 757 | /// |
---|
[1218] | 758 | bool reached(Node v) { return (*_reached)[v]; } |
---|
| 759 | |
---|
| 760 | ///@} |
---|
| 761 | }; |
---|
| 762 | |
---|
| 763 | ///Default traits class of Bfs function. |
---|
| 764 | |
---|
| 765 | ///Default traits class of Bfs function. |
---|
| 766 | ///\param GR Graph type. |
---|
| 767 | template<class GR> |
---|
| 768 | struct BfsWizardDefaultTraits |
---|
| 769 | { |
---|
| 770 | ///The graph type the algorithm runs on. |
---|
| 771 | typedef GR Graph; |
---|
| 772 | ///\brief The type of the map that stores the last |
---|
| 773 | ///edges of the shortest paths. |
---|
| 774 | /// |
---|
| 775 | ///The type of the map that stores the last |
---|
| 776 | ///edges of the shortest paths. |
---|
[2260] | 777 | ///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
---|
[774] | 778 | /// |
---|
[1218] | 779 | typedef NullMap<typename Graph::Node,typename GR::Edge> PredMap; |
---|
| 780 | ///Instantiates a PredMap. |
---|
| 781 | |
---|
| 782 | ///This function instantiates a \ref PredMap. |
---|
[1536] | 783 | ///\param g is the graph, to which we would like to define the PredMap. |
---|
[1218] | 784 | ///\todo The graph alone may be insufficient to initialize |
---|
[1536] | 785 | #ifdef DOXYGEN |
---|
| 786 | static PredMap *createPredMap(const GR &g) |
---|
| 787 | #else |
---|
[1367] | 788 | static PredMap *createPredMap(const GR &) |
---|
[1536] | 789 | #endif |
---|
[1218] | 790 | { |
---|
| 791 | return new PredMap(); |
---|
| 792 | } |
---|
| 793 | |
---|
| 794 | ///The type of the map that indicates which nodes are processed. |
---|
| 795 | |
---|
| 796 | ///The type of the map that indicates which nodes are processed. |
---|
[2260] | 797 | ///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
---|
[1218] | 798 | ///\todo named parameter to set this type, function to read and write. |
---|
| 799 | typedef NullMap<typename Graph::Node,bool> ProcessedMap; |
---|
| 800 | ///Instantiates a ProcessedMap. |
---|
| 801 | |
---|
| 802 | ///This function instantiates a \ref ProcessedMap. |
---|
[1536] | 803 | ///\param g is the graph, to which |
---|
[1218] | 804 | ///we would like to define the \ref ProcessedMap |
---|
[1536] | 805 | #ifdef DOXYGEN |
---|
| 806 | static ProcessedMap *createProcessedMap(const GR &g) |
---|
| 807 | #else |
---|
[1367] | 808 | static ProcessedMap *createProcessedMap(const GR &) |
---|
[1536] | 809 | #endif |
---|
[1218] | 810 | { |
---|
| 811 | return new ProcessedMap(); |
---|
| 812 | } |
---|
| 813 | ///The type of the map that indicates which nodes are reached. |
---|
| 814 | |
---|
| 815 | ///The type of the map that indicates which nodes are reached. |
---|
[2260] | 816 | ///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
---|
[1218] | 817 | ///\todo named parameter to set this type, function to read and write. |
---|
| 818 | typedef typename Graph::template NodeMap<bool> ReachedMap; |
---|
| 819 | ///Instantiates a ReachedMap. |
---|
| 820 | |
---|
| 821 | ///This function instantiates a \ref ReachedMap. |
---|
| 822 | ///\param G is the graph, to which |
---|
| 823 | ///we would like to define the \ref ReachedMap. |
---|
| 824 | static ReachedMap *createReachedMap(const GR &G) |
---|
| 825 | { |
---|
| 826 | return new ReachedMap(G); |
---|
| 827 | } |
---|
| 828 | ///The type of the map that stores the dists of the nodes. |
---|
| 829 | |
---|
| 830 | ///The type of the map that stores the dists of the nodes. |
---|
[2260] | 831 | ///It must meet the \ref concepts::WriteMap "WriteMap" concept. |
---|
[1218] | 832 | /// |
---|
| 833 | typedef NullMap<typename Graph::Node,int> DistMap; |
---|
| 834 | ///Instantiates a DistMap. |
---|
| 835 | |
---|
| 836 | ///This function instantiates a \ref DistMap. |
---|
[1536] | 837 | ///\param g is the graph, to which we would like to define the \ref DistMap |
---|
| 838 | #ifdef DOXYGEN |
---|
| 839 | static DistMap *createDistMap(const GR &g) |
---|
| 840 | #else |
---|
[1367] | 841 | static DistMap *createDistMap(const GR &) |
---|
[1536] | 842 | #endif |
---|
[1218] | 843 | { |
---|
| 844 | return new DistMap(); |
---|
| 845 | } |
---|
| 846 | }; |
---|
| 847 | |
---|
| 848 | /// Default traits used by \ref BfsWizard |
---|
| 849 | |
---|
| 850 | /// To make it easier to use Bfs algorithm |
---|
| 851 | ///we have created a wizard class. |
---|
| 852 | /// This \ref BfsWizard class needs default traits, |
---|
| 853 | ///as well as the \ref Bfs class. |
---|
| 854 | /// The \ref BfsWizardBase is a class to be the default traits of the |
---|
| 855 | /// \ref BfsWizard class. |
---|
| 856 | template<class GR> |
---|
| 857 | class BfsWizardBase : public BfsWizardDefaultTraits<GR> |
---|
| 858 | { |
---|
| 859 | |
---|
| 860 | typedef BfsWizardDefaultTraits<GR> Base; |
---|
| 861 | protected: |
---|
| 862 | /// Type of the nodes in the graph. |
---|
| 863 | typedef typename Base::Graph::Node Node; |
---|
| 864 | |
---|
| 865 | /// Pointer to the underlying graph. |
---|
| 866 | void *_g; |
---|
| 867 | ///Pointer to the map of reached nodes. |
---|
| 868 | void *_reached; |
---|
| 869 | ///Pointer to the map of processed nodes. |
---|
| 870 | void *_processed; |
---|
| 871 | ///Pointer to the map of predecessors edges. |
---|
| 872 | void *_pred; |
---|
| 873 | ///Pointer to the map of distances. |
---|
| 874 | void *_dist; |
---|
| 875 | ///Pointer to the source node. |
---|
| 876 | Node _source; |
---|
| 877 | |
---|
| 878 | public: |
---|
| 879 | /// Constructor. |
---|
| 880 | |
---|
| 881 | /// This constructor does not require parameters, therefore it initiates |
---|
| 882 | /// all of the attributes to default values (0, INVALID). |
---|
| 883 | BfsWizardBase() : _g(0), _reached(0), _processed(0), _pred(0), |
---|
| 884 | _dist(0), _source(INVALID) {} |
---|
| 885 | |
---|
| 886 | /// Constructor. |
---|
| 887 | |
---|
| 888 | /// This constructor requires some parameters, |
---|
| 889 | /// listed in the parameters list. |
---|
| 890 | /// Others are initiated to 0. |
---|
| 891 | /// \param g is the initial value of \ref _g |
---|
| 892 | /// \param s is the initial value of \ref _source |
---|
| 893 | BfsWizardBase(const GR &g, Node s=INVALID) : |
---|
| 894 | _g((void *)&g), _reached(0), _processed(0), _pred(0), |
---|
| 895 | _dist(0), _source(s) {} |
---|
| 896 | |
---|
| 897 | }; |
---|
| 898 | |
---|
| 899 | /// A class to make the usage of Bfs algorithm easier |
---|
| 900 | |
---|
| 901 | /// This class is created to make it easier to use Bfs algorithm. |
---|
| 902 | /// It uses the functions and features of the plain \ref Bfs, |
---|
| 903 | /// but it is much simpler to use it. |
---|
| 904 | /// |
---|
| 905 | /// Simplicity means that the way to change the types defined |
---|
| 906 | /// in the traits class is based on functions that returns the new class |
---|
| 907 | /// and not on templatable built-in classes. |
---|
| 908 | /// When using the plain \ref Bfs |
---|
| 909 | /// the new class with the modified type comes from |
---|
| 910 | /// the original class by using the :: |
---|
| 911 | /// operator. In the case of \ref BfsWizard only |
---|
| 912 | /// a function have to be called and it will |
---|
| 913 | /// return the needed class. |
---|
| 914 | /// |
---|
| 915 | /// It does not have own \ref run method. When its \ref run method is called |
---|
| 916 | /// it initiates a plain \ref Bfs class, and calls the \ref Bfs::run |
---|
| 917 | /// method of it. |
---|
| 918 | template<class TR> |
---|
| 919 | class BfsWizard : public TR |
---|
| 920 | { |
---|
| 921 | typedef TR Base; |
---|
| 922 | |
---|
| 923 | ///The type of the underlying graph. |
---|
| 924 | typedef typename TR::Graph Graph; |
---|
| 925 | //\e |
---|
| 926 | typedef typename Graph::Node Node; |
---|
| 927 | //\e |
---|
| 928 | typedef typename Graph::NodeIt NodeIt; |
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| 929 | //\e |
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| 930 | typedef typename Graph::Edge Edge; |
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| 931 | //\e |
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| 932 | typedef typename Graph::OutEdgeIt OutEdgeIt; |
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| 933 | |
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| 934 | ///\brief The type of the map that stores |
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| 935 | ///the reached nodes |
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| 936 | typedef typename TR::ReachedMap ReachedMap; |
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| 937 | ///\brief The type of the map that stores |
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| 938 | ///the processed nodes |
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| 939 | typedef typename TR::ProcessedMap ProcessedMap; |
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| 940 | ///\brief The type of the map that stores the last |
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| 941 | ///edges of the shortest paths. |
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| 942 | typedef typename TR::PredMap PredMap; |
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| 943 | ///The type of the map that stores the dists of the nodes. |
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| 944 | typedef typename TR::DistMap DistMap; |
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| 945 | |
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| 946 | public: |
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| 947 | /// Constructor. |
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| 948 | BfsWizard() : TR() {} |
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| 949 | |
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| 950 | /// Constructor that requires parameters. |
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| 951 | |
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| 952 | /// Constructor that requires parameters. |
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| 953 | /// These parameters will be the default values for the traits class. |
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| 954 | BfsWizard(const Graph &g, Node s=INVALID) : |
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| 955 | TR(g,s) {} |
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| 956 | |
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| 957 | ///Copy constructor |
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| 958 | BfsWizard(const TR &b) : TR(b) {} |
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| 959 | |
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| 960 | ~BfsWizard() {} |
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| 961 | |
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| 962 | ///Runs Bfs algorithm from a given node. |
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| 963 | |
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| 964 | ///Runs Bfs algorithm from a given node. |
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| 965 | ///The node can be given by the \ref source function. |
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| 966 | void run() |
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| 967 | { |
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| 968 | if(Base::_source==INVALID) throw UninitializedParameter(); |
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| 969 | Bfs<Graph,TR> alg(*(Graph*)Base::_g); |
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| 970 | if(Base::_reached) |
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| 971 | alg.reachedMap(*(ReachedMap*)Base::_reached); |
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| 972 | if(Base::_processed) alg.processedMap(*(ProcessedMap*)Base::_processed); |
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| 973 | if(Base::_pred) alg.predMap(*(PredMap*)Base::_pred); |
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| 974 | if(Base::_dist) alg.distMap(*(DistMap*)Base::_dist); |
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| 975 | alg.run(Base::_source); |
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| 976 | } |
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| 977 | |
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| 978 | ///Runs Bfs algorithm from the given node. |
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| 979 | |
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| 980 | ///Runs Bfs algorithm from the given node. |
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| 981 | ///\param s is the given source. |
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| 982 | void run(Node s) |
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| 983 | { |
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| 984 | Base::_source=s; |
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| 985 | run(); |
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| 986 | } |
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| 987 | |
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| 988 | template<class T> |
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| 989 | struct DefPredMapBase : public Base { |
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| 990 | typedef T PredMap; |
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[1367] | 991 | static PredMap *createPredMap(const Graph &) { return 0; }; |
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[1236] | 992 | DefPredMapBase(const TR &b) : TR(b) {} |
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[1218] | 993 | }; |
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| 994 | |
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| 995 | ///\brief \ref named-templ-param "Named parameter" |
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| 996 | ///function for setting PredMap |
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| 997 | /// |
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| 998 | /// \ref named-templ-param "Named parameter" |
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| 999 | ///function for setting PredMap |
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| 1000 | /// |
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| 1001 | template<class T> |
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| 1002 | BfsWizard<DefPredMapBase<T> > predMap(const T &t) |
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| 1003 | { |
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| 1004 | Base::_pred=(void *)&t; |
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| 1005 | return BfsWizard<DefPredMapBase<T> >(*this); |
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| 1006 | } |
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| 1007 | |
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| 1008 | |
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| 1009 | template<class T> |
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| 1010 | struct DefReachedMapBase : public Base { |
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| 1011 | typedef T ReachedMap; |
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[1367] | 1012 | static ReachedMap *createReachedMap(const Graph &) { return 0; }; |
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[1236] | 1013 | DefReachedMapBase(const TR &b) : TR(b) {} |
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[1218] | 1014 | }; |
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| 1015 | |
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| 1016 | ///\brief \ref named-templ-param "Named parameter" |
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| 1017 | ///function for setting ReachedMap |
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| 1018 | /// |
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| 1019 | /// \ref named-templ-param "Named parameter" |
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| 1020 | ///function for setting ReachedMap |
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| 1021 | /// |
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| 1022 | template<class T> |
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| 1023 | BfsWizard<DefReachedMapBase<T> > reachedMap(const T &t) |
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| 1024 | { |
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| 1025 | Base::_pred=(void *)&t; |
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| 1026 | return BfsWizard<DefReachedMapBase<T> >(*this); |
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| 1027 | } |
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| 1028 | |
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| 1029 | |
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| 1030 | template<class T> |
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| 1031 | struct DefProcessedMapBase : public Base { |
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| 1032 | typedef T ProcessedMap; |
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[1367] | 1033 | static ProcessedMap *createProcessedMap(const Graph &) { return 0; }; |
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[1236] | 1034 | DefProcessedMapBase(const TR &b) : TR(b) {} |
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[1218] | 1035 | }; |
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| 1036 | |
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| 1037 | ///\brief \ref named-templ-param "Named parameter" |
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| 1038 | ///function for setting ProcessedMap |
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| 1039 | /// |
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| 1040 | /// \ref named-templ-param "Named parameter" |
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| 1041 | ///function for setting ProcessedMap |
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| 1042 | /// |
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| 1043 | template<class T> |
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| 1044 | BfsWizard<DefProcessedMapBase<T> > processedMap(const T &t) |
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| 1045 | { |
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| 1046 | Base::_pred=(void *)&t; |
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| 1047 | return BfsWizard<DefProcessedMapBase<T> >(*this); |
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| 1048 | } |
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| 1049 | |
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| 1050 | |
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| 1051 | template<class T> |
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| 1052 | struct DefDistMapBase : public Base { |
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| 1053 | typedef T DistMap; |
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[1367] | 1054 | static DistMap *createDistMap(const Graph &) { return 0; }; |
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[1236] | 1055 | DefDistMapBase(const TR &b) : TR(b) {} |
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[1218] | 1056 | }; |
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| 1057 | |
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| 1058 | ///\brief \ref named-templ-param "Named parameter" |
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| 1059 | ///function for setting DistMap type |
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| 1060 | /// |
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| 1061 | /// \ref named-templ-param "Named parameter" |
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| 1062 | ///function for setting DistMap type |
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| 1063 | /// |
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| 1064 | template<class T> |
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| 1065 | BfsWizard<DefDistMapBase<T> > distMap(const T &t) |
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| 1066 | { |
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| 1067 | Base::_dist=(void *)&t; |
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| 1068 | return BfsWizard<DefDistMapBase<T> >(*this); |
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| 1069 | } |
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| 1070 | |
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| 1071 | /// Sets the source node, from which the Bfs algorithm runs. |
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| 1072 | |
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| 1073 | /// Sets the source node, from which the Bfs algorithm runs. |
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| 1074 | /// \param s is the source node. |
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| 1075 | BfsWizard<TR> &source(Node s) |
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| 1076 | { |
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| 1077 | Base::_source=s; |
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| 1078 | return *this; |
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| 1079 | } |
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[774] | 1080 | |
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| 1081 | }; |
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| 1082 | |
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[1218] | 1083 | ///Function type interface for Bfs algorithm. |
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| 1084 | |
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| 1085 | /// \ingroup flowalgs |
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| 1086 | ///Function type interface for Bfs algorithm. |
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| 1087 | /// |
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| 1088 | ///This function also has several |
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| 1089 | ///\ref named-templ-func-param "named parameters", |
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| 1090 | ///they are declared as the members of class \ref BfsWizard. |
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| 1091 | ///The following |
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| 1092 | ///example shows how to use these parameters. |
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| 1093 | ///\code |
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| 1094 | /// bfs(g,source).predMap(preds).run(); |
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| 1095 | ///\endcode |
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| 1096 | ///\warning Don't forget to put the \ref BfsWizard::run() "run()" |
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| 1097 | ///to the end of the parameter list. |
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| 1098 | ///\sa BfsWizard |
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| 1099 | ///\sa Bfs |
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| 1100 | template<class GR> |
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| 1101 | BfsWizard<BfsWizardBase<GR> > |
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| 1102 | bfs(const GR &g,typename GR::Node s=INVALID) |
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| 1103 | { |
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| 1104 | return BfsWizard<BfsWizardBase<GR> >(g,s); |
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| 1105 | } |
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| 1106 | |
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[921] | 1107 | } //END OF NAMESPACE LEMON |
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[774] | 1108 | |
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| 1109 | #endif |
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| 1110 | |
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