1 /* -*- C++ -*- |
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2 * src/lemon/graph_wrapper.h - Part of LEMON, a generic C++ optimization library |
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3 * |
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4 * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
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5 * (Egervary Research Group on Combinatorial Optimization, EGRES). |
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6 * |
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7 * Permission to use, modify and distribute this software is granted |
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8 * provided that this copyright notice appears in all copies. For |
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9 * precise terms see the accompanying LICENSE file. |
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10 * |
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11 * This software is provided "AS IS" with no warranty of any kind, |
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12 * express or implied, and with no claim as to its suitability for any |
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13 * purpose. |
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14 * |
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15 */ |
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16 |
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17 #ifndef LEMON_GRAPH_WRAPPER_H |
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18 #define LEMON_GRAPH_WRAPPER_H |
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19 |
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20 ///\ingroup gwrappers |
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21 ///\file |
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22 ///\brief Several graph wrappers. |
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23 /// |
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24 ///This file contains several useful graph wrapper functions. |
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25 /// |
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26 ///\author Marton Makai |
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27 |
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28 #include <lemon/invalid.h> |
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29 #include <lemon/maps.h> |
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30 #include <lemon/bits/iterable_graph_extender.h> |
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31 #include <lemon/bits/undir_graph_extender.h> |
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32 #include <iostream> |
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33 |
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34 namespace lemon { |
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35 |
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36 // Graph wrappers |
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37 |
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38 /*! |
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39 \addtogroup gwrappers |
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40 @{ |
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41 */ |
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42 |
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43 /*! |
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44 Base type for the Graph Wrappers |
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45 |
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46 \warning Graph wrappers are in even more experimental state than the other |
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47 parts of the lib. Use them at you own risk. |
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48 |
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49 This is the base type for most of LEMON graph wrappers. |
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50 This class implements a trivial graph wrapper i.e. it only wraps the |
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51 functions and types of the graph. The purpose of this class is to |
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52 make easier implementing graph wrappers. E.g. if a wrapper is |
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53 considered which differs from the wrapped graph only in some of its |
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54 functions or types, then it can be derived from GraphWrapper, and only the |
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55 differences should be implemented. |
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56 |
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57 \author Marton Makai |
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58 */ |
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59 template<typename _Graph> |
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60 class GraphWrapperBase { |
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61 public: |
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62 typedef _Graph Graph; |
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63 /// \todo Is it needed? |
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64 typedef Graph BaseGraph; |
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65 typedef Graph ParentGraph; |
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66 |
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67 protected: |
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68 Graph* graph; |
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69 GraphWrapperBase() : graph(0) { } |
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70 void setGraph(Graph& _graph) { graph=&_graph; } |
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71 |
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72 public: |
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73 GraphWrapperBase(Graph& _graph) : graph(&_graph) { } |
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74 |
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75 typedef typename Graph::Node Node; |
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76 typedef typename Graph::Edge Edge; |
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77 |
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78 void first(Node& i) const { graph->first(i); } |
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79 void first(Edge& i) const { graph->first(i); } |
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80 void firstIn(Edge& i, const Node& n) const { graph->firstIn(i, n); } |
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81 void firstOut(Edge& i, const Node& n ) const { graph->firstOut(i, n); } |
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82 |
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83 void next(Node& i) const { graph->next(i); } |
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84 void next(Edge& i) const { graph->next(i); } |
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85 void nextIn(Edge& i) const { graph->nextIn(i); } |
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86 void nextOut(Edge& i) const { graph->nextOut(i); } |
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87 |
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88 Node source(const Edge& e) const { return graph->source(e); } |
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89 Node target(const Edge& e) const { return graph->target(e); } |
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90 |
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91 int nodeNum() const { return graph->nodeNum(); } |
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92 int edgeNum() const { return graph->edgeNum(); } |
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93 |
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94 Node addNode() const { return Node(graph->addNode()); } |
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95 Edge addEdge(const Node& source, const Node& target) const { |
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96 return Edge(graph->addEdge(source, target)); } |
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97 |
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98 void erase(const Node& i) const { graph->erase(i); } |
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99 void erase(const Edge& i) const { graph->erase(i); } |
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100 |
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101 void clear() const { graph->clear(); } |
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102 |
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103 bool forward(const Edge& e) const { return graph->forward(e); } |
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104 bool backward(const Edge& e) const { return graph->backward(e); } |
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105 |
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106 int id(const Node& v) const { return graph->id(v); } |
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107 int id(const Edge& e) const { return graph->id(e); } |
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108 |
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109 Edge opposite(const Edge& e) const { return Edge(graph->opposite(e)); } |
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110 |
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111 template <typename _Value> |
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112 class NodeMap : public _Graph::template NodeMap<_Value> { |
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113 public: |
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114 typedef typename _Graph::template NodeMap<_Value> Parent; |
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115 NodeMap(const GraphWrapperBase<_Graph>& gw) : Parent(*gw.graph) { } |
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116 NodeMap(const GraphWrapperBase<_Graph>& gw, const _Value& value) |
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117 : Parent(*gw.graph, value) { } |
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118 }; |
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119 |
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120 template <typename _Value> |
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121 class EdgeMap : public _Graph::template EdgeMap<_Value> { |
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122 public: |
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123 typedef typename _Graph::template EdgeMap<_Value> Parent; |
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124 EdgeMap(const GraphWrapperBase<_Graph>& gw) : Parent(*gw.graph) { } |
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125 EdgeMap(const GraphWrapperBase<_Graph>& gw, const _Value& value) |
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126 : Parent(*gw.graph, value) { } |
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127 }; |
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128 |
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129 }; |
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130 |
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131 template <typename _Graph> |
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132 class GraphWrapper : |
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133 public IterableGraphExtender<GraphWrapperBase<_Graph> > { |
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134 public: |
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135 typedef _Graph Graph; |
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136 typedef IterableGraphExtender<GraphWrapperBase<_Graph> > Parent; |
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137 protected: |
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138 GraphWrapper() : Parent() { } |
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139 |
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140 public: |
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141 GraphWrapper(Graph& _graph) { setGraph(_graph); } |
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142 }; |
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143 |
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144 template <typename _Graph> |
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145 class RevGraphWrapperBase : public GraphWrapperBase<_Graph> { |
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146 public: |
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147 typedef _Graph Graph; |
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148 typedef GraphWrapperBase<_Graph> Parent; |
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149 protected: |
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150 RevGraphWrapperBase() : Parent() { } |
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151 public: |
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152 typedef typename Parent::Node Node; |
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153 typedef typename Parent::Edge Edge; |
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154 |
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155 // using Parent::first; |
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156 void firstIn(Edge& i, const Node& n) const { Parent::firstOut(i, n); } |
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157 void firstOut(Edge& i, const Node& n ) const { Parent::firstIn(i, n); } |
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158 |
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159 // using Parent::next; |
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160 void nextIn(Edge& i) const { Parent::nextOut(i); } |
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161 void nextOut(Edge& i) const { Parent::nextIn(i); } |
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162 |
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163 Node source(const Edge& e) const { return Parent::target(e); } |
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164 Node target(const Edge& e) const { return Parent::source(e); } |
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165 }; |
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166 |
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167 |
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168 /// A graph wrapper which reverses the orientation of the edges. |
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169 |
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170 ///\warning Graph wrappers are in even more experimental state than the other |
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171 ///parts of the lib. Use them at you own risk. |
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172 /// |
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173 /// Let \f$G=(V, A)\f$ be a directed graph and |
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174 /// suppose that a graph instange \c g of type |
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175 /// \c ListGraph implements \f$G\f$. |
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176 /// \code |
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177 /// ListGraph g; |
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178 /// \endcode |
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179 /// For each directed edge |
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180 /// \f$e\in A\f$, let \f$\bar e\f$ denote the edge obtained by |
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181 /// reversing its orientation. |
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182 /// Then RevGraphWrapper implements the graph structure with node-set |
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183 /// \f$V\f$ and edge-set |
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184 /// \f$\{\bar e : e\in A \}\f$, i.e. the graph obtained from \f$G\f$ be |
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185 /// reversing the orientation of its edges. The following code shows how |
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186 /// such an instance can be constructed. |
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187 /// \code |
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188 /// RevGraphWrapper<ListGraph> gw(g); |
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189 /// \endcode |
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190 ///\author Marton Makai |
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191 template<typename _Graph> |
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192 class RevGraphWrapper : |
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193 public IterableGraphExtender<RevGraphWrapperBase<_Graph> > { |
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194 public: |
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195 typedef _Graph Graph; |
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196 typedef IterableGraphExtender< |
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197 RevGraphWrapperBase<_Graph> > Parent; |
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198 protected: |
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199 RevGraphWrapper() { } |
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200 public: |
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201 RevGraphWrapper(_Graph& _graph) { setGraph(_graph); } |
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202 }; |
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203 |
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204 |
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205 template <typename _Graph, typename NodeFilterMap, typename EdgeFilterMap> |
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206 class SubGraphWrapperBase : public GraphWrapperBase<_Graph> { |
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207 public: |
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208 typedef _Graph Graph; |
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209 typedef GraphWrapperBase<_Graph> Parent; |
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210 protected: |
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211 NodeFilterMap* node_filter_map; |
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212 EdgeFilterMap* edge_filter_map; |
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213 SubGraphWrapperBase() : Parent(), |
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214 node_filter_map(0), edge_filter_map(0) { } |
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215 |
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216 void setNodeFilterMap(NodeFilterMap& _node_filter_map) { |
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217 node_filter_map=&_node_filter_map; |
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218 } |
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219 void setEdgeFilterMap(EdgeFilterMap& _edge_filter_map) { |
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220 edge_filter_map=&_edge_filter_map; |
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221 } |
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222 |
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223 public: |
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224 // SubGraphWrapperBase(Graph& _graph, |
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225 // NodeFilterMap& _node_filter_map, |
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226 // EdgeFilterMap& _edge_filter_map) : |
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227 // Parent(&_graph), |
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228 // node_filter_map(&node_filter_map), |
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229 // edge_filter_map(&edge_filter_map) { } |
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230 |
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231 typedef typename Parent::Node Node; |
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232 typedef typename Parent::Edge Edge; |
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233 |
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234 void first(Node& i) const { |
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235 Parent::first(i); |
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236 while (i!=INVALID && !(*node_filter_map)[i]) Parent::next(i); |
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237 } |
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238 void first(Edge& i) const { |
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239 Parent::first(i); |
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240 while (i!=INVALID && !(*edge_filter_map)[i]) Parent::next(i); |
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241 } |
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242 void firstIn(Edge& i, const Node& n) const { |
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243 Parent::firstIn(i, n); |
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244 while (i!=INVALID && !(*edge_filter_map)[i]) Parent::nextIn(i); |
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245 } |
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246 void firstOut(Edge& i, const Node& n) const { |
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247 Parent::firstOut(i, n); |
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248 while (i!=INVALID && !(*edge_filter_map)[i]) Parent::nextOut(i); |
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249 } |
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250 |
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251 void next(Node& i) const { |
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252 Parent::next(i); |
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253 while (i!=INVALID && !(*node_filter_map)[i]) Parent::next(i); |
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254 } |
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255 void next(Edge& i) const { |
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256 Parent::next(i); |
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257 while (i!=INVALID && !(*edge_filter_map)[i]) Parent::next(i); |
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258 } |
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259 void nextIn(Edge& i) const { |
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260 Parent::nextIn(i); |
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261 while (i!=INVALID && !(*edge_filter_map)[i]) Parent::nextIn(i); |
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262 } |
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263 void nextOut(Edge& i) const { |
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264 Parent::nextOut(i); |
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265 while (i!=INVALID && !(*edge_filter_map)[i]) Parent::nextOut(i); |
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266 } |
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267 |
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268 /// This function hides \c n in the graph, i.e. the iteration |
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269 /// jumps over it. This is done by simply setting the value of \c n |
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270 /// to be false in the corresponding node-map. |
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271 void hide(const Node& n) const { node_filter_map->set(n, false); } |
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272 |
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273 /// This function hides \c e in the graph, i.e. the iteration |
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274 /// jumps over it. This is done by simply setting the value of \c e |
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275 /// to be false in the corresponding edge-map. |
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276 void hide(const Edge& e) const { edge_filter_map->set(e, false); } |
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277 |
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278 /// The value of \c n is set to be true in the node-map which stores |
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279 /// hide information. If \c n was hidden previuosly, then it is shown |
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280 /// again |
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281 void unHide(const Node& n) const { node_filter_map->set(n, true); } |
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282 |
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283 /// The value of \c e is set to be true in the edge-map which stores |
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284 /// hide information. If \c e was hidden previuosly, then it is shown |
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285 /// again |
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286 void unHide(const Edge& e) const { edge_filter_map->set(e, true); } |
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287 |
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288 /// Returns true if \c n is hidden. |
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289 bool hidden(const Node& n) const { return !(*node_filter_map)[n]; } |
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290 |
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291 /// Returns true if \c n is hidden. |
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292 bool hidden(const Edge& e) const { return !(*edge_filter_map)[e]; } |
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293 |
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294 /// \warning This is a linear time operation and works only if s |
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295 /// \c Graph::NodeIt is defined. |
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296 /// \todo assign tags. |
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297 int nodeNum() const { |
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298 int i=0; |
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299 Node n; |
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300 for (first(n); n!=INVALID; next(n)) ++i; |
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301 return i; |
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302 } |
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303 |
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304 /// \warning This is a linear time operation and works only if |
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305 /// \c Graph::EdgeIt is defined. |
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306 /// \todo assign tags. |
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307 int edgeNum() const { |
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308 int i=0; |
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309 Edge e; |
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310 for (first(e); e!=INVALID; next(e)) ++i; |
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311 return i; |
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312 } |
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313 |
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314 |
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315 }; |
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316 |
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317 /*! \brief A graph wrapper for hiding nodes and edges from a graph. |
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318 |
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319 \warning Graph wrappers are in even more experimental state than the other |
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320 parts of the lib. Use them at you own risk. |
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321 |
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322 SubGraphWrapper shows the graph with filtered node-set and |
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323 edge-set. |
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324 Let \f$G=(V, A)\f$ be a directed graph |
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325 and suppose that the graph instance \c g of type ListGraph implements |
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326 \f$G\f$. |
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327 Let moreover \f$b_V\f$ and |
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328 \f$b_A\f$ be bool-valued functions resp. on the node-set and edge-set. |
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329 SubGraphWrapper<...>::NodeIt iterates |
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330 on the node-set \f$\{v\in V : b_V(v)=true\}\f$ and |
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331 SubGraphWrapper<...>::EdgeIt iterates |
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332 on the edge-set \f$\{e\in A : b_A(e)=true\}\f$. Similarly, |
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333 SubGraphWrapper<...>::OutEdgeIt and SubGraphWrapper<...>::InEdgeIt iterates |
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334 only on edges leaving and entering a specific node which have true value. |
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335 |
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336 We have to note that this does not mean that an |
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337 induced subgraph is obtained, the node-iterator cares only the filter |
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338 on the node-set, and the edge-iterators care only the filter on the |
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339 edge-set. |
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340 \code |
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341 typedef ListGraph Graph; |
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342 Graph g; |
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343 typedef Graph::Node Node; |
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344 typedef Graph::Edge Edge; |
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345 Node u=g.addNode(); //node of id 0 |
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346 Node v=g.addNode(); //node of id 1 |
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347 Node e=g.addEdge(u, v); //edge of id 0 |
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348 Node f=g.addEdge(v, u); //edge of id 1 |
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349 Graph::NodeMap<bool> nm(g, true); |
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350 nm.set(u, false); |
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351 Graph::EdgeMap<bool> em(g, true); |
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352 em.set(e, false); |
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353 typedef SubGraphWrapper<Graph, Graph::NodeMap<bool>, Graph::EdgeMap<bool> > SubGW; |
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354 SubGW gw(g, nm, em); |
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355 for (SubGW::NodeIt n(gw); n!=INVALID; ++n) std::cout << g.id(n) << std::endl; |
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356 std::cout << ":-)" << std::endl; |
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357 for (SubGW::EdgeIt e(gw); e!=INVALID; ++e) std::cout << g.id(e) << std::endl; |
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358 \endcode |
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359 The output of the above code is the following. |
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360 \code |
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361 1 |
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362 :-) |
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363 1 |
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364 \endcode |
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365 Note that \c n is of type \c SubGW::NodeIt, but it can be converted to |
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366 \c Graph::Node that is why \c g.id(n) can be applied. |
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367 |
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368 For other examples see also the documentation of NodeSubGraphWrapper and |
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369 EdgeSubGraphWrapper. |
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370 |
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371 \author Marton Makai |
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372 */ |
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373 template<typename _Graph, typename NodeFilterMap, |
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374 typename EdgeFilterMap> |
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375 class SubGraphWrapper : |
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376 public IterableGraphExtender< |
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377 SubGraphWrapperBase<_Graph, NodeFilterMap, EdgeFilterMap> > { |
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378 public: |
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379 typedef _Graph Graph; |
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380 typedef IterableGraphExtender< |
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381 SubGraphWrapperBase<_Graph, NodeFilterMap, EdgeFilterMap> > Parent; |
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382 protected: |
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383 SubGraphWrapper() { } |
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384 public: |
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385 SubGraphWrapper(_Graph& _graph, NodeFilterMap& _node_filter_map, |
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386 EdgeFilterMap& _edge_filter_map) { |
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387 setGraph(_graph); |
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388 setNodeFilterMap(_node_filter_map); |
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389 setEdgeFilterMap(_edge_filter_map); |
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390 } |
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391 }; |
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392 |
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393 |
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394 |
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395 /*! \brief A wrapper for hiding nodes from a graph. |
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396 |
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397 \warning Graph wrappers are in even more experimental state than the other |
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398 parts of the lib. Use them at you own risk. |
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399 |
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400 A wrapper for hiding nodes from a graph. |
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401 This wrapper specializes SubGraphWrapper in the way that only the node-set |
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402 can be filtered. Note that this does not mean of considering induced |
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403 subgraph, the edge-iterators consider the original edge-set. |
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404 \author Marton Makai |
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405 */ |
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406 template<typename Graph, typename NodeFilterMap> |
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407 class NodeSubGraphWrapper : |
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408 public SubGraphWrapper<Graph, NodeFilterMap, |
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409 ConstMap<typename Graph::Edge,bool> > { |
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410 public: |
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411 typedef SubGraphWrapper<Graph, NodeFilterMap, |
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412 ConstMap<typename Graph::Edge,bool> > Parent; |
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413 protected: |
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414 ConstMap<typename Graph::Edge, bool> const_true_map; |
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415 public: |
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416 NodeSubGraphWrapper(Graph& _graph, NodeFilterMap& _node_filter_map) : |
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417 Parent(), const_true_map(true) { |
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418 Parent::setGraph(_graph); |
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419 Parent::setNodeFilterMap(_node_filter_map); |
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420 Parent::setEdgeFilterMap(const_true_map); |
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421 } |
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422 }; |
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423 |
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424 |
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425 /*! \brief A wrapper for hiding edges from a graph. |
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426 |
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427 \warning Graph wrappers are in even more experimental state than the other |
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428 parts of the lib. Use them at you own risk. |
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429 |
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430 A wrapper for hiding edges from a graph. |
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431 This wrapper specializes SubGraphWrapper in the way that only the edge-set |
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432 can be filtered. The usefulness of this wrapper is demonstrated in the |
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433 problem of searching a maximum number of edge-disjoint shortest paths |
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434 between |
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435 two nodes \c s and \c t. Shortest here means being shortest w.r.t. |
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436 non-negative edge-lengths. Note that |
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437 the comprehension of the presented solution |
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438 need's some elementary knowledge from combinatorial optimization. |
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439 |
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440 If a single shortest path is to be |
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441 searched between \c s and \c t, then this can be done easily by |
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442 applying the Dijkstra algorithm. What happens, if a maximum number of |
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443 edge-disjoint shortest paths is to be computed. It can be proved that an |
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444 edge can be in a shortest path if and only if it is tight with respect to |
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445 the potential function computed by Dijkstra. Moreover, any path containing |
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446 only such edges is a shortest one. Thus we have to compute a maximum number |
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447 of edge-disjoint paths between \c s and \c t in the graph which has edge-set |
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448 all the tight edges. The computation will be demonstrated on the following |
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449 graph, which is read from a dimacs file. |
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450 |
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451 \dot |
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452 digraph lemon_dot_example { |
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453 node [ shape=ellipse, fontname=Helvetica, fontsize=10 ]; |
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454 n0 [ label="0 (s)" ]; |
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455 n1 [ label="1" ]; |
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456 n2 [ label="2" ]; |
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457 n3 [ label="3" ]; |
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458 n4 [ label="4" ]; |
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459 n5 [ label="5" ]; |
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460 n6 [ label="6 (t)" ]; |
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461 edge [ shape=ellipse, fontname=Helvetica, fontsize=10 ]; |
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462 n5 -> n6 [ label="9, length:4" ]; |
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463 n4 -> n6 [ label="8, length:2" ]; |
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464 n3 -> n5 [ label="7, length:1" ]; |
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465 n2 -> n5 [ label="6, length:3" ]; |
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466 n2 -> n6 [ label="5, length:5" ]; |
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467 n2 -> n4 [ label="4, length:2" ]; |
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468 n1 -> n4 [ label="3, length:3" ]; |
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469 n0 -> n3 [ label="2, length:1" ]; |
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470 n0 -> n2 [ label="1, length:2" ]; |
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471 n0 -> n1 [ label="0, length:3" ]; |
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472 } |
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473 \enddot |
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474 |
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475 \code |
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476 Graph g; |
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477 Node s, t; |
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478 LengthMap length(g); |
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479 |
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480 readDimacs(std::cin, g, length, s, t); |
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481 |
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482 cout << "edges with lengths (of form id, source--length->target): " << endl; |
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483 for(EdgeIt e(g); e!=INVALID; ++e) |
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484 cout << g.id(e) << ", " << g.id(g.source(e)) << "--" |
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485 << length[e] << "->" << g.id(g.target(e)) << endl; |
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486 |
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487 cout << "s: " << g.id(s) << " t: " << g.id(t) << endl; |
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488 \endcode |
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489 Next, the potential function is computed with Dijkstra. |
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490 \code |
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491 typedef Dijkstra<Graph, LengthMap> Dijkstra; |
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492 Dijkstra dijkstra(g, length); |
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493 dijkstra.run(s); |
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494 \endcode |
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495 Next, we consrtruct a map which filters the edge-set to the tight edges. |
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496 \code |
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497 typedef TightEdgeFilterMap<Graph, const Dijkstra::DistMap, LengthMap> |
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498 TightEdgeFilter; |
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499 TightEdgeFilter tight_edge_filter(g, dijkstra.distMap(), length); |
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500 |
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501 typedef EdgeSubGraphWrapper<Graph, TightEdgeFilter> SubGW; |
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502 SubGW gw(g, tight_edge_filter); |
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503 \endcode |
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504 Then, the maximum nimber of edge-disjoint \c s-\c t paths are computed |
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505 with a max flow algorithm Preflow. |
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506 \code |
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507 ConstMap<Edge, int> const_1_map(1); |
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508 Graph::EdgeMap<int> flow(g, 0); |
|
509 |
|
510 Preflow<SubGW, int, ConstMap<Edge, int>, Graph::EdgeMap<int> > |
|
511 preflow(gw, s, t, const_1_map, flow); |
|
512 preflow.run(); |
|
513 \endcode |
|
514 Last, the output is: |
|
515 \code |
|
516 cout << "maximum number of edge-disjoint shortest path: " |
|
517 << preflow.flowValue() << endl; |
|
518 cout << "edges of the maximum number of edge-disjoint shortest s-t paths: " |
|
519 << endl; |
|
520 for(EdgeIt e(g); e!=INVALID; ++e) |
|
521 if (flow[e]) |
|
522 cout << " " << g.id(g.source(e)) << "--" |
|
523 << length[e] << "->" << g.id(g.target(e)) << endl; |
|
524 \endcode |
|
525 The program has the following (expected :-)) output: |
|
526 \code |
|
527 edges with lengths (of form id, source--length->target): |
|
528 9, 5--4->6 |
|
529 8, 4--2->6 |
|
530 7, 3--1->5 |
|
531 6, 2--3->5 |
|
532 5, 2--5->6 |
|
533 4, 2--2->4 |
|
534 3, 1--3->4 |
|
535 2, 0--1->3 |
|
536 1, 0--2->2 |
|
537 0, 0--3->1 |
|
538 s: 0 t: 6 |
|
539 maximum number of edge-disjoint shortest path: 2 |
|
540 edges of the maximum number of edge-disjoint shortest s-t paths: |
|
541 9, 5--4->6 |
|
542 8, 4--2->6 |
|
543 7, 3--1->5 |
|
544 4, 2--2->4 |
|
545 2, 0--1->3 |
|
546 1, 0--2->2 |
|
547 \endcode |
|
548 |
|
549 \author Marton Makai |
|
550 */ |
|
551 template<typename Graph, typename EdgeFilterMap> |
|
552 class EdgeSubGraphWrapper : |
|
553 public SubGraphWrapper<Graph, ConstMap<typename Graph::Node,bool>, |
|
554 EdgeFilterMap> { |
|
555 public: |
|
556 typedef SubGraphWrapper<Graph, ConstMap<typename Graph::Node,bool>, |
|
557 EdgeFilterMap> Parent; |
|
558 protected: |
|
559 ConstMap<typename Graph::Node, bool> const_true_map; |
|
560 public: |
|
561 EdgeSubGraphWrapper(Graph& _graph, EdgeFilterMap& _edge_filter_map) : |
|
562 Parent(), const_true_map(true) { |
|
563 Parent::setGraph(_graph); |
|
564 Parent::setNodeFilterMap(const_true_map); |
|
565 Parent::setEdgeFilterMap(_edge_filter_map); |
|
566 } |
|
567 }; |
|
568 |
|
569 template <typename _Graph> |
|
570 class UndirGraphWrapperBase : |
|
571 public UndirGraphExtender<GraphWrapperBase<_Graph> > { |
|
572 public: |
|
573 typedef _Graph Graph; |
|
574 typedef UndirGraphExtender<GraphWrapperBase<_Graph> > Parent; |
|
575 protected: |
|
576 UndirGraphWrapperBase() : Parent() { } |
|
577 public: |
|
578 typedef typename Parent::UndirEdge UndirEdge; |
|
579 typedef typename Parent::Edge Edge; |
|
580 |
|
581 /// \bug Why cant an edge say that it is forward or not??? |
|
582 /// By this, a pointer to the graph have to be stored |
|
583 /// The implementation |
|
584 template <typename T> |
|
585 class EdgeMap { |
|
586 protected: |
|
587 const UndirGraphWrapperBase<_Graph>* g; |
|
588 template <typename TT> friend class EdgeMap; |
|
589 typename _Graph::template EdgeMap<T> forward_map, backward_map; |
|
590 public: |
|
591 typedef T Value; |
|
592 typedef Edge Key; |
|
593 |
|
594 EdgeMap(const UndirGraphWrapperBase<_Graph>& _g) : g(&_g), |
|
595 forward_map(*(g->graph)), backward_map(*(g->graph)) { } |
|
596 |
|
597 EdgeMap(const UndirGraphWrapperBase<_Graph>& _g, T a) : g(&_g), |
|
598 forward_map(*(g->graph), a), backward_map(*(g->graph), a) { } |
|
599 |
|
600 void set(Edge e, T a) { |
|
601 if (g->forward(e)) |
|
602 forward_map.set(e, a); |
|
603 else |
|
604 backward_map.set(e, a); |
|
605 } |
|
606 |
|
607 T operator[](Edge e) const { |
|
608 if (g->forward(e)) |
|
609 return forward_map[e]; |
|
610 else |
|
611 return backward_map[e]; |
|
612 } |
|
613 }; |
|
614 |
|
615 template <typename T> |
|
616 class UndirEdgeMap { |
|
617 template <typename TT> friend class UndirEdgeMap; |
|
618 typename _Graph::template EdgeMap<T> map; |
|
619 public: |
|
620 typedef T Value; |
|
621 typedef UndirEdge Key; |
|
622 |
|
623 UndirEdgeMap(const UndirGraphWrapperBase<_Graph>& g) : |
|
624 map(*(g.graph)) { } |
|
625 |
|
626 UndirEdgeMap(const UndirGraphWrapperBase<_Graph>& g, T a) : |
|
627 map(*(g.graph), a) { } |
|
628 |
|
629 void set(UndirEdge e, T a) { |
|
630 map.set(e, a); |
|
631 } |
|
632 |
|
633 T operator[](UndirEdge e) const { |
|
634 return map[e]; |
|
635 } |
|
636 }; |
|
637 |
|
638 }; |
|
639 |
|
640 /// \brief An undirected graph is made from a directed graph by a wrapper |
|
641 /// |
|
642 /// Undocumented, untested!!! |
|
643 /// If somebody knows nice demo application, let's polulate it. |
|
644 /// |
|
645 /// \author Marton Makai |
|
646 template<typename _Graph> |
|
647 class UndirGraphWrapper : |
|
648 public IterableUndirGraphExtender< |
|
649 UndirGraphWrapperBase<_Graph> > { |
|
650 public: |
|
651 typedef _Graph Graph; |
|
652 typedef IterableUndirGraphExtender< |
|
653 UndirGraphWrapperBase<_Graph> > Parent; |
|
654 protected: |
|
655 UndirGraphWrapper() { } |
|
656 public: |
|
657 UndirGraphWrapper(_Graph& _graph) { |
|
658 setGraph(_graph); |
|
659 } |
|
660 }; |
|
661 |
|
662 |
|
663 template <typename _Graph, |
|
664 typename ForwardFilterMap, typename BackwardFilterMap> |
|
665 class SubBidirGraphWrapperBase : public GraphWrapperBase<_Graph> { |
|
666 public: |
|
667 typedef _Graph Graph; |
|
668 typedef GraphWrapperBase<_Graph> Parent; |
|
669 protected: |
|
670 ForwardFilterMap* forward_filter; |
|
671 BackwardFilterMap* backward_filter; |
|
672 SubBidirGraphWrapperBase() : Parent(), |
|
673 forward_filter(0), backward_filter(0) { } |
|
674 |
|
675 void setForwardFilterMap(ForwardFilterMap& _forward_filter) { |
|
676 forward_filter=&_forward_filter; |
|
677 } |
|
678 void setBackwardFilterMap(BackwardFilterMap& _backward_filter) { |
|
679 backward_filter=&_backward_filter; |
|
680 } |
|
681 |
|
682 public: |
|
683 // SubGraphWrapperBase(Graph& _graph, |
|
684 // NodeFilterMap& _node_filter_map, |
|
685 // EdgeFilterMap& _edge_filter_map) : |
|
686 // Parent(&_graph), |
|
687 // node_filter_map(&node_filter_map), |
|
688 // edge_filter_map(&edge_filter_map) { } |
|
689 |
|
690 typedef typename Parent::Node Node; |
|
691 typedef typename _Graph::Edge GraphEdge; |
|
692 template <typename T> class EdgeMap; |
|
693 /// SubBidirGraphWrapperBase<..., ..., ...>::Edge is inherited from |
|
694 /// _Graph::Edge. It contains an extra bool flag which is true |
|
695 /// if and only if the |
|
696 /// edge is the backward version of the original edge. |
|
697 class Edge : public _Graph::Edge { |
|
698 friend class SubBidirGraphWrapperBase< |
|
699 Graph, ForwardFilterMap, BackwardFilterMap>; |
|
700 template<typename T> friend class EdgeMap; |
|
701 protected: |
|
702 bool backward; //true, iff backward |
|
703 public: |
|
704 Edge() { } |
|
705 /// \todo =false is needed, or causes problems? |
|
706 /// If \c _backward is false, then we get an edge corresponding to the |
|
707 /// original one, otherwise its oppositely directed pair is obtained. |
|
708 Edge(const typename _Graph::Edge& e, bool _backward/*=false*/) : |
|
709 _Graph::Edge(e), backward(_backward) { } |
|
710 Edge(Invalid i) : _Graph::Edge(i), backward(true) { } |
|
711 bool operator==(const Edge& v) const { |
|
712 return (this->backward==v.backward && |
|
713 static_cast<typename _Graph::Edge>(*this)== |
|
714 static_cast<typename _Graph::Edge>(v)); |
|
715 } |
|
716 bool operator!=(const Edge& v) const { |
|
717 return (this->backward!=v.backward || |
|
718 static_cast<typename _Graph::Edge>(*this)!= |
|
719 static_cast<typename _Graph::Edge>(v)); |
|
720 } |
|
721 }; |
|
722 |
|
723 void first(Node& i) const { |
|
724 Parent::first(i); |
|
725 } |
|
726 |
|
727 void first(Edge& i) const { |
|
728 Parent::first(i); |
|
729 i.backward=false; |
|
730 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
731 !(*forward_filter)[i]) Parent::next(i); |
|
732 if (*static_cast<GraphEdge*>(&i)==INVALID) { |
|
733 Parent::first(i); |
|
734 i.backward=true; |
|
735 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
736 !(*backward_filter)[i]) Parent::next(i); |
|
737 } |
|
738 } |
|
739 |
|
740 void firstIn(Edge& i, const Node& n) const { |
|
741 Parent::firstIn(i, n); |
|
742 i.backward=false; |
|
743 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
744 !(*forward_filter)[i]) Parent::nextIn(i); |
|
745 if (*static_cast<GraphEdge*>(&i)==INVALID) { |
|
746 Parent::firstOut(i, n); |
|
747 i.backward=true; |
|
748 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
749 !(*backward_filter)[i]) Parent::nextOut(i); |
|
750 } |
|
751 } |
|
752 |
|
753 void firstOut(Edge& i, const Node& n) const { |
|
754 Parent::firstOut(i, n); |
|
755 i.backward=false; |
|
756 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
757 !(*forward_filter)[i]) Parent::nextOut(i); |
|
758 if (*static_cast<GraphEdge*>(&i)==INVALID) { |
|
759 Parent::firstIn(i, n); |
|
760 i.backward=true; |
|
761 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
762 !(*backward_filter)[i]) Parent::nextIn(i); |
|
763 } |
|
764 } |
|
765 |
|
766 void next(Node& i) const { |
|
767 Parent::next(i); |
|
768 } |
|
769 |
|
770 void next(Edge& i) const { |
|
771 if (!(i.backward)) { |
|
772 Parent::next(i); |
|
773 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
774 !(*forward_filter)[i]) Parent::next(i); |
|
775 if (*static_cast<GraphEdge*>(&i)==INVALID) { |
|
776 Parent::first(i); |
|
777 i.backward=true; |
|
778 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
779 !(*backward_filter)[i]) Parent::next(i); |
|
780 } |
|
781 } else { |
|
782 Parent::next(i); |
|
783 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
784 !(*backward_filter)[i]) Parent::next(i); |
|
785 } |
|
786 } |
|
787 |
|
788 void nextIn(Edge& i) const { |
|
789 if (!(i.backward)) { |
|
790 Node n=Parent::target(i); |
|
791 Parent::nextIn(i); |
|
792 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
793 !(*forward_filter)[i]) Parent::nextIn(i); |
|
794 if (*static_cast<GraphEdge*>(&i)==INVALID) { |
|
795 Parent::firstOut(i, n); |
|
796 i.backward=true; |
|
797 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
798 !(*backward_filter)[i]) Parent::nextOut(i); |
|
799 } |
|
800 } else { |
|
801 Parent::nextOut(i); |
|
802 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
803 !(*backward_filter)[i]) Parent::nextOut(i); |
|
804 } |
|
805 } |
|
806 |
|
807 void nextOut(Edge& i) const { |
|
808 if (!(i.backward)) { |
|
809 Node n=Parent::source(i); |
|
810 Parent::nextOut(i); |
|
811 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
812 !(*forward_filter)[i]) Parent::nextOut(i); |
|
813 if (*static_cast<GraphEdge*>(&i)==INVALID) { |
|
814 Parent::firstIn(i, n); |
|
815 i.backward=true; |
|
816 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
817 !(*backward_filter)[i]) Parent::nextIn(i); |
|
818 } |
|
819 } else { |
|
820 Parent::nextIn(i); |
|
821 while (*static_cast<GraphEdge*>(&i)!=INVALID && |
|
822 !(*backward_filter)[i]) Parent::nextIn(i); |
|
823 } |
|
824 } |
|
825 |
|
826 Node source(Edge e) const { |
|
827 return ((!e.backward) ? this->graph->source(e) : this->graph->target(e)); } |
|
828 Node target(Edge e) const { |
|
829 return ((!e.backward) ? this->graph->target(e) : this->graph->source(e)); } |
|
830 |
|
831 /// Gives back the opposite edge. |
|
832 Edge opposite(const Edge& e) const { |
|
833 Edge f=e; |
|
834 f.backward=!f.backward; |
|
835 return f; |
|
836 } |
|
837 |
|
838 /// \warning This is a linear time operation and works only if |
|
839 /// \c Graph::EdgeIt is defined. |
|
840 /// \todo hmm |
|
841 int edgeNum() const { |
|
842 int i=0; |
|
843 Edge e; |
|
844 for (first(e); e!=INVALID; next(e)) ++i; |
|
845 return i; |
|
846 } |
|
847 |
|
848 bool forward(const Edge& e) const { return !e.backward; } |
|
849 bool backward(const Edge& e) const { return e.backward; } |
|
850 |
|
851 template <typename T> |
|
852 /// \c SubBidirGraphWrapperBase<..., ..., ...>::EdgeMap contains two |
|
853 /// _Graph::EdgeMap one for the forward edges and |
|
854 /// one for the backward edges. |
|
855 class EdgeMap { |
|
856 template <typename TT> friend class EdgeMap; |
|
857 typename _Graph::template EdgeMap<T> forward_map, backward_map; |
|
858 public: |
|
859 typedef T Value; |
|
860 typedef Edge Key; |
|
861 |
|
862 EdgeMap(const SubBidirGraphWrapperBase<_Graph, |
|
863 ForwardFilterMap, BackwardFilterMap>& g) : |
|
864 forward_map(*(g.graph)), backward_map(*(g.graph)) { } |
|
865 |
|
866 EdgeMap(const SubBidirGraphWrapperBase<_Graph, |
|
867 ForwardFilterMap, BackwardFilterMap>& g, T a) : |
|
868 forward_map(*(g.graph), a), backward_map(*(g.graph), a) { } |
|
869 |
|
870 void set(Edge e, T a) { |
|
871 if (!e.backward) |
|
872 forward_map.set(e, a); |
|
873 else |
|
874 backward_map.set(e, a); |
|
875 } |
|
876 |
|
877 // typename _Graph::template EdgeMap<T>::ConstReference |
|
878 // operator[](Edge e) const { |
|
879 // if (!e.backward) |
|
880 // return forward_map[e]; |
|
881 // else |
|
882 // return backward_map[e]; |
|
883 // } |
|
884 |
|
885 // typename _Graph::template EdgeMap<T>::Reference |
|
886 T operator[](Edge e) const { |
|
887 if (!e.backward) |
|
888 return forward_map[e]; |
|
889 else |
|
890 return backward_map[e]; |
|
891 } |
|
892 |
|
893 void update() { |
|
894 forward_map.update(); |
|
895 backward_map.update(); |
|
896 } |
|
897 }; |
|
898 |
|
899 }; |
|
900 |
|
901 |
|
902 ///\brief A wrapper for composing a subgraph of a |
|
903 /// bidirected graph made from a directed one. |
|
904 /// |
|
905 /// A wrapper for composing a subgraph of a |
|
906 /// bidirected graph made from a directed one. |
|
907 /// |
|
908 ///\warning Graph wrappers are in even more experimental state than the other |
|
909 ///parts of the lib. Use them at you own risk. |
|
910 /// |
|
911 /// Let \f$G=(V, A)\f$ be a directed graph and for each directed edge |
|
912 /// \f$e\in A\f$, let \f$\bar e\f$ denote the edge obtained by |
|
913 /// reversing its orientation. We are given moreover two bool valued |
|
914 /// maps on the edge-set, |
|
915 /// \f$forward\_filter\f$, and \f$backward\_filter\f$. |
|
916 /// SubBidirGraphWrapper implements the graph structure with node-set |
|
917 /// \f$V\f$ and edge-set |
|
918 /// \f$\{e : e\in A \mbox{ and } forward\_filter(e) \mbox{ is true}\}+\{\bar e : e\in A \mbox{ and } backward\_filter(e) \mbox{ is true}\}\f$. |
|
919 /// The purpose of writing + instead of union is because parallel |
|
920 /// edges can arise. (Similarly, antiparallel edges also can arise). |
|
921 /// In other words, a subgraph of the bidirected graph obtained, which |
|
922 /// is given by orienting the edges of the original graph in both directions. |
|
923 /// As the oppositely directed edges are logically different, |
|
924 /// the maps are able to attach different values for them. |
|
925 /// |
|
926 /// An example for such a construction is \c RevGraphWrapper where the |
|
927 /// forward_filter is everywhere false and the backward_filter is |
|
928 /// everywhere true. We note that for sake of efficiency, |
|
929 /// \c RevGraphWrapper is implemented in a different way. |
|
930 /// But BidirGraphWrapper is obtained from |
|
931 /// SubBidirGraphWrapper by considering everywhere true |
|
932 /// valued maps both for forward_filter and backward_filter. |
|
933 /// |
|
934 /// The most important application of SubBidirGraphWrapper |
|
935 /// is ResGraphWrapper, which stands for the residual graph in directed |
|
936 /// flow and circulation problems. |
|
937 /// As wrappers usually, the SubBidirGraphWrapper implements the |
|
938 /// above mentioned graph structure without its physical storage, |
|
939 /// that is the whole stuff is stored in constant memory. |
|
940 template<typename _Graph, |
|
941 typename ForwardFilterMap, typename BackwardFilterMap> |
|
942 class SubBidirGraphWrapper : |
|
943 public IterableGraphExtender< |
|
944 SubBidirGraphWrapperBase<_Graph, ForwardFilterMap, BackwardFilterMap> > { |
|
945 public: |
|
946 typedef _Graph Graph; |
|
947 typedef IterableGraphExtender< |
|
948 SubBidirGraphWrapperBase< |
|
949 _Graph, ForwardFilterMap, BackwardFilterMap> > Parent; |
|
950 protected: |
|
951 SubBidirGraphWrapper() { } |
|
952 public: |
|
953 SubBidirGraphWrapper(_Graph& _graph, ForwardFilterMap& _forward_filter, |
|
954 BackwardFilterMap& _backward_filter) { |
|
955 setGraph(_graph); |
|
956 setForwardFilterMap(_forward_filter); |
|
957 setBackwardFilterMap(_backward_filter); |
|
958 } |
|
959 }; |
|
960 |
|
961 |
|
962 |
|
963 ///\brief A wrapper for composing bidirected graph from a directed one. |
|
964 /// |
|
965 ///\warning Graph wrappers are in even more experimental state than the other |
|
966 ///parts of the lib. Use them at you own risk. |
|
967 /// |
|
968 /// A wrapper for composing bidirected graph from a directed one. |
|
969 /// A bidirected graph is composed over the directed one without physical |
|
970 /// storage. As the oppositely directed edges are logically different ones |
|
971 /// the maps are able to attach different values for them. |
|
972 template<typename Graph> |
|
973 class BidirGraphWrapper : |
|
974 public SubBidirGraphWrapper< |
|
975 Graph, |
|
976 ConstMap<typename Graph::Edge, bool>, |
|
977 ConstMap<typename Graph::Edge, bool> > { |
|
978 public: |
|
979 typedef SubBidirGraphWrapper< |
|
980 Graph, |
|
981 ConstMap<typename Graph::Edge, bool>, |
|
982 ConstMap<typename Graph::Edge, bool> > Parent; |
|
983 protected: |
|
984 ConstMap<typename Graph::Edge, bool> cm; |
|
985 |
|
986 BidirGraphWrapper() : Parent(), cm(true) { |
|
987 Parent::setForwardFilterMap(cm); |
|
988 Parent::setBackwardFilterMap(cm); |
|
989 } |
|
990 public: |
|
991 BidirGraphWrapper(Graph& _graph) : Parent(), cm(true) { |
|
992 Parent::setGraph(_graph); |
|
993 Parent::setForwardFilterMap(cm); |
|
994 Parent::setBackwardFilterMap(cm); |
|
995 } |
|
996 |
|
997 int edgeNum() const { |
|
998 return 2*this->graph->edgeNum(); |
|
999 } |
|
1000 // KEEP_MAPS(Parent, BidirGraphWrapper); |
|
1001 }; |
|
1002 |
|
1003 |
|
1004 template<typename Graph, typename Number, |
|
1005 typename CapacityMap, typename FlowMap> |
|
1006 class ResForwardFilter { |
|
1007 // const Graph* graph; |
|
1008 const CapacityMap* capacity; |
|
1009 const FlowMap* flow; |
|
1010 public: |
|
1011 ResForwardFilter(/*const Graph& _graph, */ |
|
1012 const CapacityMap& _capacity, const FlowMap& _flow) : |
|
1013 /*graph(&_graph),*/ capacity(&_capacity), flow(&_flow) { } |
|
1014 ResForwardFilter() : /*graph(0),*/ capacity(0), flow(0) { } |
|
1015 void setCapacity(const CapacityMap& _capacity) { capacity=&_capacity; } |
|
1016 void setFlow(const FlowMap& _flow) { flow=&_flow; } |
|
1017 bool operator[](const typename Graph::Edge& e) const { |
|
1018 return (Number((*flow)[e]) < Number((*capacity)[e])); |
|
1019 } |
|
1020 }; |
|
1021 |
|
1022 template<typename Graph, typename Number, |
|
1023 typename CapacityMap, typename FlowMap> |
|
1024 class ResBackwardFilter { |
|
1025 const CapacityMap* capacity; |
|
1026 const FlowMap* flow; |
|
1027 public: |
|
1028 ResBackwardFilter(/*const Graph& _graph,*/ |
|
1029 const CapacityMap& _capacity, const FlowMap& _flow) : |
|
1030 /*graph(&_graph),*/ capacity(&_capacity), flow(&_flow) { } |
|
1031 ResBackwardFilter() : /*graph(0),*/ capacity(0), flow(0) { } |
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1032 void setCapacity(const CapacityMap& _capacity) { capacity=&_capacity; } |
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1033 void setFlow(const FlowMap& _flow) { flow=&_flow; } |
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1034 bool operator[](const typename Graph::Edge& e) const { |
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1035 return (Number(0) < Number((*flow)[e])); |
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1036 } |
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1037 }; |
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1038 |
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1039 |
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1040 /*! \brief A wrapper for composing the residual graph for directed flow and circulation problems. |
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1041 |
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1042 A wrapper for composing the residual graph for directed flow and circulation problems. |
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1043 Let \f$G=(V, A)\f$ be a directed graph and let \f$F\f$ be a |
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1044 number type. Let moreover |
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1045 \f$f,c:A\to F\f$, be functions on the edge-set. |
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1046 In the appications of ResGraphWrapper, \f$f\f$ usually stands for a flow |
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1047 and \f$c\f$ for a capacity function. |
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1048 Suppose that a graph instange \c g of type |
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1049 \c ListGraph implements \f$G\f$. |
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1050 \code |
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1051 ListGraph g; |
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1052 \endcode |
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1053 Then RevGraphWrapper implements the graph structure with node-set |
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1054 \f$V\f$ and edge-set \f$A_{forward}\cup A_{backward}\f$, where |
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1055 \f$A_{forward}=\{uv : uv\in A, f(uv)<c(uv)\}\f$ and |
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1056 \f$A_{backward}=\{vu : uv\in A, f(uv)>0\}\f$, |
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1057 i.e. the so called residual graph. |
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1058 When we take the union \f$A_{forward}\cup A_{backward}\f$, |
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1059 multilicities are counted, i.e. if an edge is in both |
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1060 \f$A_{forward}\f$ and \f$A_{backward}\f$, then in the wrapper it |
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1061 appears twice. |
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1062 The following code shows how |
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1063 such an instance can be constructed. |
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1064 \code |
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1065 typedef ListGraph Graph; |
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1066 Graph::EdgeMap<int> f(g); |
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1067 Graph::EdgeMap<int> c(g); |
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1068 ResGraphWrapper<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> > gw(g); |
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1069 \endcode |
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1070 \author Marton Makai |
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1071 */ |
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1072 template<typename Graph, typename Number, |
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1073 typename CapacityMap, typename FlowMap> |
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1074 class ResGraphWrapper : |
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1075 public SubBidirGraphWrapper< |
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1076 Graph, |
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1077 ResForwardFilter<Graph, Number, CapacityMap, FlowMap>, |
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1078 ResBackwardFilter<Graph, Number, CapacityMap, FlowMap> > { |
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1079 public: |
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1080 typedef SubBidirGraphWrapper< |
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1081 Graph, |
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1082 ResForwardFilter<Graph, Number, CapacityMap, FlowMap>, |
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1083 ResBackwardFilter<Graph, Number, CapacityMap, FlowMap> > Parent; |
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1084 protected: |
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1085 const CapacityMap* capacity; |
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1086 FlowMap* flow; |
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1087 ResForwardFilter<Graph, Number, CapacityMap, FlowMap> forward_filter; |
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1088 ResBackwardFilter<Graph, Number, CapacityMap, FlowMap> backward_filter; |
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1089 ResGraphWrapper() : Parent(), |
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1090 capacity(0), flow(0) { } |
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1091 void setCapacityMap(const CapacityMap& _capacity) { |
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1092 capacity=&_capacity; |
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1093 forward_filter.setCapacity(_capacity); |
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1094 backward_filter.setCapacity(_capacity); |
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1095 } |
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1096 void setFlowMap(FlowMap& _flow) { |
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1097 flow=&_flow; |
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1098 forward_filter.setFlow(_flow); |
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1099 backward_filter.setFlow(_flow); |
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1100 } |
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1101 public: |
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1102 ResGraphWrapper(Graph& _graph, const CapacityMap& _capacity, |
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1103 FlowMap& _flow) : |
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1104 Parent(), capacity(&_capacity), flow(&_flow), |
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1105 forward_filter(/*_graph,*/ _capacity, _flow), |
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1106 backward_filter(/*_graph,*/ _capacity, _flow) { |
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1107 Parent::setGraph(_graph); |
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1108 Parent::setForwardFilterMap(forward_filter); |
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1109 Parent::setBackwardFilterMap(backward_filter); |
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1110 } |
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1111 |
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1112 typedef typename Parent::Edge Edge; |
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1113 |
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1114 void augment(const Edge& e, Number a) const { |
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1115 if (Parent::forward(e)) |
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1116 flow->set(e, (*flow)[e]+a); |
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1117 else |
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1118 flow->set(e, (*flow)[e]-a); |
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1119 } |
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1120 |
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1121 /// \brief Residual capacity map. |
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1122 /// |
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1123 /// In generic residual graphs the residual capacity can be obtained |
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1124 /// as a map. |
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1125 class ResCap { |
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1126 protected: |
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1127 const ResGraphWrapper<Graph, Number, CapacityMap, FlowMap>* res_graph; |
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1128 public: |
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1129 typedef Number Value; |
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1130 typedef Edge Key; |
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1131 ResCap(const ResGraphWrapper<Graph, Number, CapacityMap, FlowMap>& |
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1132 _res_graph) : res_graph(&_res_graph) { } |
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1133 Number operator[](const Edge& e) const { |
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1134 if (res_graph->forward(e)) |
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1135 return (*(res_graph->capacity))[e]-(*(res_graph->flow))[e]; |
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1136 else |
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1137 return (*(res_graph->flow))[e]; |
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1138 } |
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1139 }; |
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1140 |
|
1141 // KEEP_MAPS(Parent, ResGraphWrapper); |
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1142 }; |
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1143 |
|
1144 |
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1145 |
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1146 template <typename _Graph, typename FirstOutEdgesMap> |
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1147 class ErasingFirstGraphWrapperBase : public GraphWrapperBase<_Graph> { |
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1148 public: |
|
1149 typedef _Graph Graph; |
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1150 typedef GraphWrapperBase<_Graph> Parent; |
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1151 protected: |
|
1152 FirstOutEdgesMap* first_out_edges; |
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1153 ErasingFirstGraphWrapperBase() : Parent(), |
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1154 first_out_edges(0) { } |
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1155 |
|
1156 void setFirstOutEdgesMap(FirstOutEdgesMap& _first_out_edges) { |
|
1157 first_out_edges=&_first_out_edges; |
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1158 } |
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1159 |
|
1160 public: |
|
1161 |
|
1162 typedef typename Parent::Node Node; |
|
1163 typedef typename Parent::Edge Edge; |
|
1164 |
|
1165 void firstOut(Edge& i, const Node& n) const { |
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1166 i=(*first_out_edges)[n]; |
|
1167 } |
|
1168 |
|
1169 void erase(const Edge& e) const { |
|
1170 Node n=source(e); |
|
1171 Edge f=e; |
|
1172 Parent::nextOut(f); |
|
1173 first_out_edges->set(n, f); |
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1174 } |
|
1175 }; |
|
1176 |
|
1177 |
|
1178 /// For blocking flows. |
|
1179 |
|
1180 ///\warning Graph wrappers are in even more experimental state than the other |
|
1181 ///parts of the lib. Use them at you own risk. |
|
1182 /// |
|
1183 /// This graph wrapper is used for on-the-fly |
|
1184 /// Dinits blocking flow computations. |
|
1185 /// For each node, an out-edge is stored which is used when the |
|
1186 /// \code |
|
1187 /// OutEdgeIt& first(OutEdgeIt&, const Node&) |
|
1188 /// \endcode |
|
1189 /// is called. |
|
1190 /// |
|
1191 /// \author Marton Makai |
|
1192 template <typename _Graph, typename FirstOutEdgesMap> |
|
1193 class ErasingFirstGraphWrapper : |
|
1194 public IterableGraphExtender< |
|
1195 ErasingFirstGraphWrapperBase<_Graph, FirstOutEdgesMap> > { |
|
1196 public: |
|
1197 typedef _Graph Graph; |
|
1198 typedef IterableGraphExtender< |
|
1199 ErasingFirstGraphWrapperBase<_Graph, FirstOutEdgesMap> > Parent; |
|
1200 ErasingFirstGraphWrapper(Graph& _graph, |
|
1201 FirstOutEdgesMap& _first_out_edges) { |
|
1202 setGraph(_graph); |
|
1203 setFirstOutEdgesMap(_first_out_edges); |
|
1204 } |
|
1205 |
|
1206 }; |
|
1207 |
|
1208 ///@} |
|
1209 |
|
1210 } //namespace lemon |
|
1211 |
|
1212 #endif //LEMON_GRAPH_WRAPPER_H |
|
1213 |
|