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) 2004 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
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5 | * (Egervary Combinatorial Optimization Research Group, 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/iterable_graph_extender.h> |
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31 | #include <iostream> |
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32 | |
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33 | namespace lemon { |
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34 | |
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35 | // Graph wrappers |
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36 | |
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37 | /*! \addtogroup gwrappers |
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38 | The main parts of LEMON are the different graph structures, |
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39 | generic graph algorithms, graph concepts which couple these, and |
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40 | graph wrappers. While the previous ones are more or less clear, the |
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41 | latter notion needs further explanation. |
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42 | Graph wrappers are graph classes which serve for considering graph |
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43 | structures in different ways. A short example makes the notion much |
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44 | clearer. |
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45 | Suppose that we have an instance \c g of a directed graph |
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46 | type say \c ListGraph and an algorithm |
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47 | \code template<typename Graph> int algorithm(const Graph&); \endcode |
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48 | is needed to run on the reversely oriented graph. |
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49 | It may be expensive (in time or in memory usage) to copy |
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50 | \c g with the reverse orientation. |
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51 | Thus, a wrapper class |
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52 | \code template<typename Graph> class RevGraphWrapper; \endcode is used. |
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53 | The code looks as follows |
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54 | \code |
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55 | ListGraph g; |
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56 | RevGraphWrapper<ListGraph> rgw(g); |
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57 | int result=algorithm(rgw); |
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58 | \endcode |
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59 | After running the algorithm, the original graph \c g |
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60 | remains untouched. Thus the graph wrapper used above is to consider the |
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61 | original graph with reverse orientation. |
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62 | This techniques gives rise to an elegant code, and |
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63 | based on stable graph wrappers, complex algorithms can be |
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64 | implemented easily. |
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65 | In flow, circulation and bipartite matching problems, the residual |
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66 | graph is of particular importance. Combining a wrapper implementing |
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67 | this, shortest path algorithms and minimum mean cycle algorithms, |
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68 | a range of weighted and cardinality optimization algorithms can be |
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69 | obtained. For lack of space, for other examples, |
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70 | the interested user is referred to the detailed documentation of graph |
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71 | wrappers. |
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72 | The behavior of graph wrappers can be very different. Some of them keep |
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73 | capabilities of the original graph while in other cases this would be |
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74 | meaningless. This means that the concepts that they are a model of depend |
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75 | on the graph wrapper, and the wrapped graph(s). |
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76 | If an edge of \c rgw is deleted, this is carried out by |
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77 | deleting the corresponding edge of \c g. But for a residual |
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78 | graph, this operation has no sense. |
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79 | Let we stand one more example here to simplify your work. |
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80 | wrapper class |
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81 | \code template<typename Graph> class RevGraphWrapper; \endcode |
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82 | has constructor |
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83 | <tt> RevGraphWrapper(Graph& _g)</tt>. |
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84 | This means that in a situation, |
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85 | when a <tt> const ListGraph& </tt> reference to a graph is given, |
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86 | then it have to be instantiated with <tt>Graph=const ListGraph</tt>. |
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87 | \code |
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88 | int algorithm1(const ListGraph& g) { |
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89 | RevGraphWrapper<const ListGraph> rgw(g); |
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90 | return algorithm2(rgw); |
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91 | } |
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92 | \endcode |
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93 | |
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94 | \addtogroup gwrappers |
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95 | @{ |
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96 | |
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97 | Base type for the Graph Wrappers |
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98 | |
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99 | \warning Graph wrappers are in even more experimental state than the other |
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100 | parts of the lib. Use them at you own risk. |
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101 | |
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102 | This is the base type for most of LEMON graph wrappers. |
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103 | This class implements a trivial graph wrapper i.e. it only wraps the |
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104 | functions and types of the graph. The purpose of this class is to |
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105 | make easier implementing graph wrappers. E.g. if a wrapper is |
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106 | considered which differs from the wrapped graph only in some of its |
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107 | functions or types, then it can be derived from GraphWrapper, and only the |
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108 | differences should be implemented. |
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109 | |
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110 | \author Marton Makai |
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111 | */ |
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112 | template<typename _Graph> |
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113 | class GraphWrapperBase { |
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114 | public: |
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115 | typedef _Graph Graph; |
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116 | /// \todo Is it needed? |
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117 | typedef Graph BaseGraph; |
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118 | typedef Graph ParentGraph; |
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119 | |
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120 | protected: |
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121 | Graph* graph; |
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122 | GraphWrapperBase() : graph(0) { } |
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123 | void setGraph(Graph& _graph) { graph=&_graph; } |
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124 | |
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125 | public: |
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126 | GraphWrapperBase(Graph& _graph) : graph(&_graph) { } |
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127 | |
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128 | typedef typename Graph::Node Node; |
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129 | typedef typename Graph::Edge Edge; |
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130 | |
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131 | void first(Node& i) const { graph->first(i); } |
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132 | void first(Edge& i) const { graph->first(i); } |
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133 | void firstIn(Edge& i, const Node& n) const { graph->firstIn(i, n); } |
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134 | void firstOut(Edge& i, const Node& n ) const { graph->firstOut(i, n); } |
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135 | |
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136 | void next(Node& i) const { graph->next(i); } |
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137 | void next(Edge& i) const { graph->next(i); } |
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138 | void nextIn(Edge& i) const { graph->nextIn(i); } |
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139 | void nextOut(Edge& i) const { graph->nextOut(i); } |
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140 | |
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141 | Node source(const Edge& e) const { return graph->source(e); } |
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142 | Node target(const Edge& e) const { return graph->target(e); } |
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143 | |
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144 | int nodeNum() const { return graph->nodeNum(); } |
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145 | int edgeNum() const { return graph->edgeNum(); } |
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146 | |
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147 | Node addNode() const { return Node(graph->addNode()); } |
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148 | Edge addEdge(const Node& source, const Node& target) const { |
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149 | return Edge(graph->addEdge(source, target)); } |
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150 | |
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151 | void erase(const Node& i) const { graph->erase(i); } |
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152 | void erase(const Edge& i) const { graph->erase(i); } |
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153 | |
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154 | void clear() const { graph->clear(); } |
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155 | |
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156 | bool forward(const Edge& e) const { return graph->forward(e); } |
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157 | bool backward(const Edge& e) const { return graph->backward(e); } |
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158 | |
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159 | int id(const Node& v) const { return graph->id(v); } |
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160 | int id(const Edge& e) const { return graph->id(e); } |
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161 | |
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162 | Edge opposite(const Edge& e) const { return Edge(graph->opposite(e)); } |
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163 | |
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164 | template <typename _Value> |
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165 | class NodeMap : public _Graph::template NodeMap<_Value> { |
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166 | public: |
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167 | typedef typename _Graph::template NodeMap<_Value> Parent; |
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168 | NodeMap(const GraphWrapperBase<_Graph>& gw) : Parent(*gw.graph) { } |
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169 | NodeMap(const GraphWrapperBase<_Graph>& gw, const _Value& value) |
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170 | : Parent(*gw.graph, value) { } |
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171 | }; |
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172 | |
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173 | template <typename _Value> |
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174 | class EdgeMap : public _Graph::template EdgeMap<_Value> { |
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175 | public: |
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176 | typedef typename _Graph::template EdgeMap<_Value> Parent; |
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177 | EdgeMap(const GraphWrapperBase<_Graph>& gw) : Parent(*gw.graph) { } |
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178 | EdgeMap(const GraphWrapperBase<_Graph>& gw, const _Value& value) |
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179 | : Parent(*gw.graph, value) { } |
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180 | }; |
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181 | |
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182 | }; |
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183 | |
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184 | template <typename _Graph> |
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185 | class GraphWrapper : |
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186 | public IterableGraphExtender<GraphWrapperBase<_Graph> > { |
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187 | public: |
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188 | typedef _Graph Graph; |
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189 | typedef IterableGraphExtender<GraphWrapperBase<_Graph> > Parent; |
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190 | protected: |
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191 | GraphWrapper() : Parent() { } |
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192 | |
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193 | public: |
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194 | GraphWrapper(Graph& _graph) { setGraph(_graph); } |
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195 | }; |
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196 | |
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197 | template <typename _Graph> |
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198 | class RevGraphWrapperBase : public GraphWrapperBase<_Graph> { |
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199 | public: |
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200 | typedef _Graph Graph; |
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201 | typedef GraphWrapperBase<_Graph> Parent; |
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202 | protected: |
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203 | RevGraphWrapperBase() : Parent() { } |
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204 | public: |
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205 | typedef typename Parent::Node Node; |
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206 | typedef typename Parent::Edge Edge; |
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207 | |
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208 | using Parent::first; |
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209 | void firstIn(Edge& i, const Node& n) const { Parent::firstOut(i, n); } |
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210 | void firstOut(Edge& i, const Node& n ) const { Parent::firstIn(i, n); } |
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211 | |
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212 | using Parent::next; |
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213 | void nextIn(Edge& i) const { Parent::nextOut(i); } |
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214 | void nextOut(Edge& i) const { Parent::nextIn(i); } |
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215 | |
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216 | Node source(const Edge& e) const { return Parent::target(e); } |
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217 | Node target(const Edge& e) const { return Parent::source(e); } |
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218 | }; |
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219 | |
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220 | |
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221 | /// A graph wrapper which reverses the orientation of the edges. |
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222 | |
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223 | ///\warning Graph wrappers are in even more experimental state than the other |
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224 | ///parts of the lib. Use them at you own risk. |
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225 | /// |
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226 | /// Let \f$G=(V, A)\f$ be a directed graph and |
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227 | /// suppose that a graph instange \c g of type |
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228 | /// \c ListGraph implements \f$G\f$. |
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229 | /// \code |
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230 | /// ListGraph g; |
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231 | /// \endcode |
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232 | /// For each directed edge |
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233 | /// \f$e\in A\f$, let \f$\bar e\f$ denote the edge obtained by |
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234 | /// reversing its orientation. |
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235 | /// Then RevGraphWrapper implements the graph structure with node-set |
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236 | /// \f$V\f$ and edge-set |
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237 | /// \f$\{\bar e : e\in A \}\f$, i.e. the graph obtained from \f$G\f$ be |
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238 | /// reversing the orientation of its edges. The following code shows how |
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239 | /// such an instance can be constructed. |
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240 | /// \code |
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241 | /// RevGraphWrapper<ListGraph> gw(g); |
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242 | /// \endcode |
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243 | ///\author Marton Makai |
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244 | template<typename _Graph> |
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245 | class RevGraphWrapper : |
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246 | public IterableGraphExtender<RevGraphWrapperBase<_Graph> > { |
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247 | public: |
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248 | typedef _Graph Graph; |
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249 | typedef IterableGraphExtender< |
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250 | RevGraphWrapperBase<_Graph> > Parent; |
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251 | protected: |
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252 | RevGraphWrapper() { } |
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253 | public: |
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254 | RevGraphWrapper(_Graph& _graph) { setGraph(_graph); } |
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255 | }; |
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256 | |
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257 | |
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258 | template <typename _Graph, typename NodeFilterMap, typename EdgeFilterMap> |
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259 | class SubGraphWrapperBase : public GraphWrapperBase<_Graph> { |
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260 | public: |
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261 | typedef _Graph Graph; |
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262 | typedef GraphWrapperBase<_Graph> Parent; |
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263 | protected: |
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264 | NodeFilterMap* node_filter_map; |
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265 | EdgeFilterMap* edge_filter_map; |
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266 | SubGraphWrapperBase() : Parent(), |
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267 | node_filter_map(0), edge_filter_map(0) { } |
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268 | |
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269 | void setNodeFilterMap(NodeFilterMap& _node_filter_map) { |
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270 | node_filter_map=&_node_filter_map; |
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271 | } |
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272 | void setEdgeFilterMap(EdgeFilterMap& _edge_filter_map) { |
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273 | edge_filter_map=&_edge_filter_map; |
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274 | } |
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275 | |
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276 | public: |
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277 | // SubGraphWrapperBase(Graph& _graph, |
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278 | // NodeFilterMap& _node_filter_map, |
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279 | // EdgeFilterMap& _edge_filter_map) : |
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280 | // Parent(&_graph), |
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281 | // node_filter_map(&node_filter_map), |
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282 | // edge_filter_map(&edge_filter_map) { } |
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283 | |
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284 | typedef typename Parent::Node Node; |
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285 | typedef typename Parent::Edge Edge; |
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286 | |
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287 | void first(Node& i) const { |
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288 | Parent::first(i); |
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289 | while (i!=INVALID && !(*node_filter_map)[i]) Parent::next(i); |
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290 | } |
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291 | void first(Edge& i) const { |
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292 | Parent::first(i); |
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293 | while (i!=INVALID && !(*edge_filter_map)[i]) Parent::next(i); |
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294 | } |
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295 | void firstIn(Edge& i, const Node& n) const { |
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296 | Parent::firstIn(i, n); |
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297 | while (i!=INVALID && !(*edge_filter_map)[i]) Parent::nextIn(i); |
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298 | } |
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299 | void firstOut(Edge& i, const Node& n) const { |
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300 | Parent::firstOut(i, n); |
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301 | while (i!=INVALID && !(*edge_filter_map)[i]) Parent::nextOut(i); |
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302 | } |
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303 | |
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304 | void next(Node& i) const { |
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305 | Parent::next(i); |
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306 | while (i!=INVALID && !(*node_filter_map)[i]) Parent::next(i); |
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307 | } |
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308 | void next(Edge& i) const { |
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309 | Parent::next(i); |
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310 | while (i!=INVALID && !(*edge_filter_map)[i]) Parent::next(i); |
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311 | } |
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312 | void nextIn(Edge& i) const { |
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313 | Parent::nextIn(i); |
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314 | while (i!=INVALID && !(*edge_filter_map)[i]) Parent::nextIn(i); |
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315 | } |
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316 | void nextOut(Edge& i) const { |
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317 | Parent::nextOut(i); |
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318 | while (i!=INVALID && !(*edge_filter_map)[i]) Parent::nextOut(i); |
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319 | } |
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320 | |
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321 | /// This function hides \c n in the graph, i.e. the iteration |
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322 | /// jumps over it. This is done by simply setting the value of \c n |
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323 | /// to be false in the corresponding node-map. |
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324 | void hide(const Node& n) const { node_filter_map->set(n, false); } |
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325 | |
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326 | /// This function hides \c e in the graph, i.e. the iteration |
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327 | /// jumps over it. This is done by simply setting the value of \c e |
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328 | /// to be false in the corresponding edge-map. |
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329 | void hide(const Edge& e) const { edge_filter_map->set(e, false); } |
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330 | |
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331 | /// The value of \c n is set to be true in the node-map which stores |
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332 | /// hide information. If \c n was hidden previuosly, then it is shown |
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333 | /// again |
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334 | void unHide(const Node& n) const { node_filter_map->set(n, true); } |
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335 | |
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336 | /// The value of \c e is set to be true in the edge-map which stores |
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337 | /// hide information. If \c e was hidden previuosly, then it is shown |
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338 | /// again |
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339 | void unHide(const Edge& e) const { edge_filter_map->set(e, true); } |
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340 | |
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341 | /// Returns true if \c n is hidden. |
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342 | bool hidden(const Node& n) const { return !(*node_filter_map)[n]; } |
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343 | |
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344 | /// Returns true if \c n is hidden. |
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345 | bool hidden(const Edge& e) const { return !(*edge_filter_map)[e]; } |
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346 | |
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347 | /// \warning This is a linear time operation and works only if s |
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348 | /// \c Graph::NodeIt is defined. |
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349 | /// \todo assign tags. |
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350 | int nodeNum() const { |
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351 | int i=0; |
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352 | Node n; |
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353 | for (first(n); n!=INVALID; next(n)) ++i; |
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354 | return i; |
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355 | } |
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356 | |
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357 | /// \warning This is a linear time operation and works only if |
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358 | /// \c Graph::EdgeIt is defined. |
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359 | /// \todo assign tags. |
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360 | int edgeNum() const { |
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361 | int i=0; |
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362 | Edge e; |
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363 | for (first(e); e!=INVALID; next(e)) ++i; |
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364 | return i; |
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365 | } |
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366 | |
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367 | |
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368 | }; |
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369 | |
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370 | /*! \brief A graph wrapper for hiding nodes and edges from a graph. |
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371 | |
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372 | \warning Graph wrappers are in even more experimental state than the other |
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373 | parts of the lib. Use them at you own risk. |
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374 | |
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375 | This wrapper shows a graph with filtered node-set and |
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376 | edge-set. |
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377 | Given a bool-valued map on the node-set and one on |
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378 | the edge-set of the graph, the iterators show only the objects |
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379 | having true value. We have to note that this does not mean that an |
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380 | induced subgraph is obtained, the node-iterator cares only the filter |
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381 | on the node-set, and the edge-iterators care only the filter on the |
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382 | edge-set. |
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383 | \code |
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384 | typedef SmartGraph Graph; |
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385 | Graph g; |
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386 | typedef Graph::Node Node; |
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387 | typedef Graph::Edge Edge; |
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388 | Node u=g.addNode(); //node of id 0 |
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389 | Node v=g.addNode(); //node of id 1 |
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390 | Node e=g.addEdge(u, v); //edge of id 0 |
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391 | Node f=g.addEdge(v, u); //edge of id 1 |
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392 | Graph::NodeMap<bool> nm(g, true); |
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393 | nm.set(u, false); |
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394 | Graph::EdgeMap<bool> em(g, true); |
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395 | em.set(e, false); |
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396 | typedef SubGraphWrapper<Graph, Graph::NodeMap<bool>, Graph::EdgeMap<bool> > SubGW; |
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397 | SubGW gw(g, nm, em); |
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398 | for (SubGW::NodeIt n(gw); n!=INVALID; ++n) std::cout << g.id(n) << std::endl; |
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399 | std::cout << ":-)" << std::endl; |
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400 | for (SubGW::EdgeIt e(gw); e!=INVALID; ++e) std::cout << g.id(e) << std::endl; |
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401 | \endcode |
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402 | The output of the above code is the following. |
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403 | \code |
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404 | 1 |
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405 | :-) |
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406 | 1 |
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407 | \endcode |
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408 | Note that \c n is of type \c SubGW::NodeIt, but it can be converted to |
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409 | \c Graph::Node that is why \c g.id(n) can be applied. |
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410 | |
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411 | For other examples see also the documentation of NodeSubGraphWrapper and |
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412 | EdgeSubGraphWrapper. |
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413 | |
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414 | \author Marton Makai |
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415 | */ |
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416 | template<typename _Graph, typename NodeFilterMap, |
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417 | typename EdgeFilterMap> |
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418 | class SubGraphWrapper : |
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419 | public IterableGraphExtender< |
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420 | SubGraphWrapperBase<_Graph, NodeFilterMap, EdgeFilterMap> > { |
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421 | public: |
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422 | typedef _Graph Graph; |
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423 | typedef IterableGraphExtender< |
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424 | SubGraphWrapperBase<_Graph, NodeFilterMap, EdgeFilterMap> > Parent; |
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425 | protected: |
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426 | SubGraphWrapper() { } |
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427 | public: |
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428 | SubGraphWrapper(_Graph& _graph, NodeFilterMap& _node_filter_map, |
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429 | EdgeFilterMap& _edge_filter_map) { |
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430 | setGraph(_graph); |
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431 | setNodeFilterMap(_node_filter_map); |
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432 | setEdgeFilterMap(_edge_filter_map); |
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433 | } |
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434 | }; |
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435 | |
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436 | |
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437 | |
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438 | /*! \brief A wrapper for hiding nodes from a graph. |
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439 | |
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440 | \warning Graph wrappers are in even more experimental state than the other |
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441 | parts of the lib. Use them at you own risk. |
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442 | |
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443 | A wrapper for hiding nodes from a graph. |
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444 | This wrapper specializes SubGraphWrapper in the way that only the node-set |
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445 | can be filtered. Note that this does not mean of considering induced |
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446 | subgraph, the edge-iterators consider the original edge-set. |
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447 | \author Marton Makai |
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448 | */ |
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449 | template<typename Graph, typename NodeFilterMap> |
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450 | class NodeSubGraphWrapper : |
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451 | public SubGraphWrapper<Graph, NodeFilterMap, |
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452 | ConstMap<typename Graph::Edge,bool> > { |
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453 | public: |
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454 | typedef SubGraphWrapper<Graph, NodeFilterMap, |
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455 | ConstMap<typename Graph::Edge,bool> > Parent; |
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456 | protected: |
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457 | ConstMap<typename Graph::Edge, bool> const_true_map; |
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458 | public: |
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459 | NodeSubGraphWrapper(Graph& _graph, NodeFilterMap& _node_filter_map) : |
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460 | Parent(), const_true_map(true) { |
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461 | Parent::setGraph(_graph); |
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462 | Parent::setNodeFilterMap(_node_filter_map); |
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463 | Parent::setEdgeFilterMap(const_true_map); |
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464 | } |
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465 | }; |
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466 | |
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467 | |
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468 | /*! \brief A wrapper for hiding edges from a graph. |
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469 | |
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470 | \warning Graph wrappers are in even more experimental state than the other |
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471 | parts of the lib. Use them at you own risk. |
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472 | |
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473 | A wrapper for hiding edges from a graph. |
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474 | This wrapper specializes SubGraphWrapper in the way that only the edge-set |
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475 | can be filtered. The usefulness of this wrapper is demonstrated in the |
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476 | problem of searching a maximum number of edge-disjoint shortest paths |
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477 | between |
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478 | two nodes \c s and \c t. Shortest here means being shortest w.r.t. |
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479 | non-negative edge-lengths. Note that |
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480 | the comprehension of the presented solution |
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481 | need's some knowledge from elementary combinatorial optimization. |
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482 | |
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483 | If a single shortest path is to be |
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484 | searched between two nodes \c s and \c t, then this can be done easily by |
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485 | applying the Dijkstra algorithm class. What happens, if a maximum number of |
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486 | edge-disjoint shortest paths is to be computed. It can be proved that an |
---|
487 | edge can be in a shortest path if and only if it is tight with respect to |
---|
488 | the potential function computed by Dijkstra. Moreover, any path containing |
---|
489 | only such edges is a shortest one. Thus we have to compute a maximum number |
---|
490 | of edge-disjoint paths between \c s and \c t in the graph which has edge-set |
---|
491 | all the tight edges. The computation will be demonstrated on the following |
---|
492 | graph, which is read from a dimacs file. |
---|
493 | |
---|
494 | \dot |
---|
495 | digraph lemon_dot_example { |
---|
496 | node [ shape=ellipse, fontname=Helvetica, fontsize=10 ]; |
---|
497 | n0 [ label="0 (s)" ]; |
---|
498 | n1 [ label="1" ]; |
---|
499 | n2 [ label="2" ]; |
---|
500 | n3 [ label="3" ]; |
---|
501 | n4 [ label="4" ]; |
---|
502 | n5 [ label="5" ]; |
---|
503 | n6 [ label="6 (t)" ]; |
---|
504 | edge [ shape=ellipse, fontname=Helvetica, fontsize=10 ]; |
---|
505 | n5 -> n6 [ label="9, length:4" ]; |
---|
506 | n4 -> n6 [ label="8, length:2" ]; |
---|
507 | n3 -> n5 [ label="7, length:1" ]; |
---|
508 | n2 -> n5 [ label="6, length:3" ]; |
---|
509 | n2 -> n6 [ label="5, length:5" ]; |
---|
510 | n2 -> n4 [ label="4, length:2" ]; |
---|
511 | n1 -> n4 [ label="3, length:3" ]; |
---|
512 | n0 -> n3 [ label="2, length:1" ]; |
---|
513 | n0 -> n2 [ label="1, length:2" ]; |
---|
514 | n0 -> n1 [ label="0, length:3" ]; |
---|
515 | } |
---|
516 | \enddot |
---|
517 | |
---|
518 | \code |
---|
519 | Graph g; |
---|
520 | Node s, t; |
---|
521 | LengthMap length(g); |
---|
522 | |
---|
523 | readDimacs(std::cin, g, length, s, t); |
---|
524 | |
---|
525 | cout << "edges with lengths (of form id, source--length->target): " << endl; |
---|
526 | for(EdgeIt e(g); e!=INVALID; ++e) |
---|
527 | cout << g.id(e) << ", " << g.id(g.source(e)) << "--" |
---|
528 | << length[e] << "->" << g.id(g.target(e)) << endl; |
---|
529 | |
---|
530 | cout << "s: " << g.id(s) << " t: " << g.id(t) << endl; |
---|
531 | \endcode |
---|
532 | Next, the potential function is computed with Dijkstra. |
---|
533 | \code |
---|
534 | typedef Dijkstra<Graph, LengthMap> Dijkstra; |
---|
535 | Dijkstra dijkstra(g, length); |
---|
536 | dijkstra.run(s); |
---|
537 | \endcode |
---|
538 | Next, we consrtruct a map which filters the edge-set to the tight edges. |
---|
539 | \code |
---|
540 | typedef TightEdgeFilterMap<Graph, const Dijkstra::DistMap, LengthMap> |
---|
541 | TightEdgeFilter; |
---|
542 | TightEdgeFilter tight_edge_filter(g, dijkstra.distMap(), length); |
---|
543 | |
---|
544 | typedef EdgeSubGraphWrapper<Graph, TightEdgeFilter> SubGW; |
---|
545 | SubGW gw(g, tight_edge_filter); |
---|
546 | \endcode |
---|
547 | Then, the maximum nimber of edge-disjoint \c s-\c t paths are computed |
---|
548 | with a max flow algorithm Preflow. |
---|
549 | \code |
---|
550 | ConstMap<Edge, int> const_1_map(1); |
---|
551 | Graph::EdgeMap<int> flow(g, 0); |
---|
552 | |
---|
553 | Preflow<SubGW, int, ConstMap<Edge, int>, Graph::EdgeMap<int> > |
---|
554 | preflow(gw, s, t, const_1_map, flow); |
---|
555 | preflow.run(); |
---|
556 | \endcode |
---|
557 | Last, the output is: |
---|
558 | \code |
---|
559 | cout << "maximum number of edge-disjoint shortest path: " |
---|
560 | << preflow.flowValue() << endl; |
---|
561 | cout << "edges of the maximum number of edge-disjoint shortest s-t paths: " |
---|
562 | << endl; |
---|
563 | for(EdgeIt e(g); e!=INVALID; ++e) |
---|
564 | if (flow[e]) |
---|
565 | cout << " " << g.id(g.source(e)) << "--" |
---|
566 | << length[e] << "->" << g.id(g.target(e)) << endl; |
---|
567 | \endcode |
---|
568 | The program has the following (expected :-)) output: |
---|
569 | \code |
---|
570 | edges with lengths (of form id, source--length->target): |
---|
571 | 9, 5--4->6 |
---|
572 | 8, 4--2->6 |
---|
573 | 7, 3--1->5 |
---|
574 | 6, 2--3->5 |
---|
575 | 5, 2--5->6 |
---|
576 | 4, 2--2->4 |
---|
577 | 3, 1--3->4 |
---|
578 | 2, 0--1->3 |
---|
579 | 1, 0--2->2 |
---|
580 | 0, 0--3->1 |
---|
581 | s: 0 t: 6 |
---|
582 | maximum number of edge-disjoint shortest path: 2 |
---|
583 | edges of the maximum number of edge-disjoint shortest s-t paths: |
---|
584 | 9, 5--4->6 |
---|
585 | 8, 4--2->6 |
---|
586 | 7, 3--1->5 |
---|
587 | 4, 2--2->4 |
---|
588 | 2, 0--1->3 |
---|
589 | 1, 0--2->2 |
---|
590 | \endcode |
---|
591 | |
---|
592 | \author Marton Makai |
---|
593 | */ |
---|
594 | template<typename Graph, typename EdgeFilterMap> |
---|
595 | class EdgeSubGraphWrapper : |
---|
596 | public SubGraphWrapper<Graph, ConstMap<typename Graph::Node,bool>, |
---|
597 | EdgeFilterMap> { |
---|
598 | public: |
---|
599 | typedef SubGraphWrapper<Graph, ConstMap<typename Graph::Node,bool>, |
---|
600 | EdgeFilterMap> Parent; |
---|
601 | protected: |
---|
602 | ConstMap<typename Graph::Node, bool> const_true_map; |
---|
603 | public: |
---|
604 | EdgeSubGraphWrapper(Graph& _graph, EdgeFilterMap& _edge_filter_map) : |
---|
605 | Parent(), const_true_map(true) { |
---|
606 | Parent::setGraph(_graph); |
---|
607 | Parent::setNodeFilterMap(const_true_map); |
---|
608 | Parent::setEdgeFilterMap(_edge_filter_map); |
---|
609 | } |
---|
610 | }; |
---|
611 | |
---|
612 | |
---|
613 | template<typename Graph> |
---|
614 | class UndirGraphWrapper : public GraphWrapper<Graph> { |
---|
615 | public: |
---|
616 | typedef GraphWrapper<Graph> Parent; |
---|
617 | protected: |
---|
618 | UndirGraphWrapper() : GraphWrapper<Graph>() { } |
---|
619 | |
---|
620 | public: |
---|
621 | typedef typename GraphWrapper<Graph>::Node Node; |
---|
622 | typedef typename GraphWrapper<Graph>::NodeIt NodeIt; |
---|
623 | typedef typename GraphWrapper<Graph>::Edge Edge; |
---|
624 | typedef typename GraphWrapper<Graph>::EdgeIt EdgeIt; |
---|
625 | |
---|
626 | UndirGraphWrapper(Graph& _graph) : GraphWrapper<Graph>(_graph) { } |
---|
627 | |
---|
628 | class OutEdgeIt { |
---|
629 | friend class UndirGraphWrapper<Graph>; |
---|
630 | bool out_or_in; //true iff out |
---|
631 | typename Graph::OutEdgeIt out; |
---|
632 | typename Graph::InEdgeIt in; |
---|
633 | public: |
---|
634 | OutEdgeIt() { } |
---|
635 | OutEdgeIt(const Invalid& i) : Edge(i) { } |
---|
636 | OutEdgeIt(const UndirGraphWrapper<Graph>& _G, const Node& _n) { |
---|
637 | out_or_in=true; _G.graph->first(out, _n); |
---|
638 | if (!(_G.graph->valid(out))) { out_or_in=false; _G.graph->first(in, _n); } |
---|
639 | } |
---|
640 | operator Edge() const { |
---|
641 | if (out_or_in) return Edge(out); else return Edge(in); |
---|
642 | } |
---|
643 | }; |
---|
644 | |
---|
645 | typedef OutEdgeIt InEdgeIt; |
---|
646 | |
---|
647 | using GraphWrapper<Graph>::first; |
---|
648 | OutEdgeIt& first(OutEdgeIt& i, const Node& p) const { |
---|
649 | i=OutEdgeIt(*this, p); return i; |
---|
650 | } |
---|
651 | |
---|
652 | using GraphWrapper<Graph>::next; |
---|
653 | |
---|
654 | OutEdgeIt& next(OutEdgeIt& e) const { |
---|
655 | if (e.out_or_in) { |
---|
656 | typename Graph::Node n=this->graph->source(e.out); |
---|
657 | this->graph->next(e.out); |
---|
658 | if (!this->graph->valid(e.out)) { |
---|
659 | e.out_or_in=false; this->graph->first(e.in, n); } |
---|
660 | } else { |
---|
661 | this->graph->next(e.in); |
---|
662 | } |
---|
663 | return e; |
---|
664 | } |
---|
665 | |
---|
666 | Node aNode(const OutEdgeIt& e) const { |
---|
667 | if (e.out_or_in) return this->graph->source(e); else |
---|
668 | return this->graph->target(e); } |
---|
669 | Node bNode(const OutEdgeIt& e) const { |
---|
670 | if (e.out_or_in) return this->graph->target(e); else |
---|
671 | return this->graph->source(e); } |
---|
672 | |
---|
673 | // KEEP_MAPS(Parent, UndirGraphWrapper); |
---|
674 | |
---|
675 | }; |
---|
676 | |
---|
677 | // /// \brief An undirected graph template. |
---|
678 | // /// |
---|
679 | // ///\warning Graph wrappers are in even more experimental state than the other |
---|
680 | // ///parts of the lib. Use them at your own risk. |
---|
681 | // /// |
---|
682 | // /// An undirected graph template. |
---|
683 | // /// This class works as an undirected graph and a directed graph of |
---|
684 | // /// class \c Graph is used for the physical storage. |
---|
685 | // /// \ingroup graphs |
---|
686 | template<typename Graph> |
---|
687 | class UndirGraph : public UndirGraphWrapper<Graph> { |
---|
688 | typedef UndirGraphWrapper<Graph> Parent; |
---|
689 | protected: |
---|
690 | Graph gr; |
---|
691 | public: |
---|
692 | UndirGraph() : UndirGraphWrapper<Graph>() { |
---|
693 | Parent::setGraph(gr); |
---|
694 | } |
---|
695 | |
---|
696 | // KEEP_MAPS(Parent, UndirGraph); |
---|
697 | }; |
---|
698 | |
---|
699 | |
---|
700 | template <typename _Graph, |
---|
701 | typename ForwardFilterMap, typename BackwardFilterMap> |
---|
702 | class SubBidirGraphWrapperBase : public GraphWrapperBase<_Graph> { |
---|
703 | public: |
---|
704 | typedef _Graph Graph; |
---|
705 | typedef GraphWrapperBase<_Graph> Parent; |
---|
706 | protected: |
---|
707 | ForwardFilterMap* forward_filter; |
---|
708 | BackwardFilterMap* backward_filter; |
---|
709 | SubBidirGraphWrapperBase() : Parent(), |
---|
710 | forward_filter(0), backward_filter(0) { } |
---|
711 | |
---|
712 | void setForwardFilterMap(ForwardFilterMap& _forward_filter) { |
---|
713 | forward_filter=&_forward_filter; |
---|
714 | } |
---|
715 | void setBackwardFilterMap(BackwardFilterMap& _backward_filter) { |
---|
716 | backward_filter=&_backward_filter; |
---|
717 | } |
---|
718 | |
---|
719 | public: |
---|
720 | // SubGraphWrapperBase(Graph& _graph, |
---|
721 | // NodeFilterMap& _node_filter_map, |
---|
722 | // EdgeFilterMap& _edge_filter_map) : |
---|
723 | // Parent(&_graph), |
---|
724 | // node_filter_map(&node_filter_map), |
---|
725 | // edge_filter_map(&edge_filter_map) { } |
---|
726 | |
---|
727 | typedef typename Parent::Node Node; |
---|
728 | typedef typename _Graph::Edge GraphEdge; |
---|
729 | template <typename T> class EdgeMap; |
---|
730 | /// SubBidirGraphWrapperBase<..., ..., ...>::Edge is inherited from |
---|
731 | /// _Graph::Edge. It contains an extra bool flag which is true |
---|
732 | /// if and only if the |
---|
733 | /// edge is the backward version of the original edge. |
---|
734 | class Edge : public _Graph::Edge { |
---|
735 | friend class SubBidirGraphWrapperBase< |
---|
736 | Graph, ForwardFilterMap, BackwardFilterMap>; |
---|
737 | template<typename T> friend class EdgeMap; |
---|
738 | protected: |
---|
739 | bool backward; //true, iff backward |
---|
740 | public: |
---|
741 | Edge() { } |
---|
742 | /// \todo =false is needed, or causes problems? |
---|
743 | /// If \c _backward is false, then we get an edge corresponding to the |
---|
744 | /// original one, otherwise its oppositely directed pair is obtained. |
---|
745 | Edge(const typename _Graph::Edge& e, bool _backward/*=false*/) : |
---|
746 | _Graph::Edge(e), backward(_backward) { } |
---|
747 | Edge(Invalid i) : _Graph::Edge(i), backward(true) { } |
---|
748 | bool operator==(const Edge& v) const { |
---|
749 | return (this->backward==v.backward && |
---|
750 | static_cast<typename _Graph::Edge>(*this)== |
---|
751 | static_cast<typename _Graph::Edge>(v)); |
---|
752 | } |
---|
753 | bool operator!=(const Edge& v) const { |
---|
754 | return (this->backward!=v.backward || |
---|
755 | static_cast<typename _Graph::Edge>(*this)!= |
---|
756 | static_cast<typename _Graph::Edge>(v)); |
---|
757 | } |
---|
758 | }; |
---|
759 | |
---|
760 | void first(Node& i) const { |
---|
761 | Parent::first(i); |
---|
762 | } |
---|
763 | |
---|
764 | void first(Edge& i) const { |
---|
765 | Parent::first(i); |
---|
766 | i.backward=false; |
---|
767 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
768 | !(*forward_filter)[i]) Parent::next(i); |
---|
769 | if (*static_cast<GraphEdge*>(&i)==INVALID) { |
---|
770 | Parent::first(i); |
---|
771 | i.backward=true; |
---|
772 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
773 | !(*backward_filter)[i]) Parent::next(i); |
---|
774 | } |
---|
775 | } |
---|
776 | |
---|
777 | void firstIn(Edge& i, const Node& n) const { |
---|
778 | Parent::firstIn(i, n); |
---|
779 | i.backward=false; |
---|
780 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
781 | !(*forward_filter)[i]) Parent::nextOut(i); |
---|
782 | if (*static_cast<GraphEdge*>(&i)==INVALID) { |
---|
783 | Parent::firstOut(i, n); |
---|
784 | i.backward=true; |
---|
785 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
786 | !(*backward_filter)[i]) Parent::nextOut(i); |
---|
787 | } |
---|
788 | } |
---|
789 | |
---|
790 | void firstOut(Edge& i, const Node& n) const { |
---|
791 | Parent::firstOut(i, n); |
---|
792 | i.backward=false; |
---|
793 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
794 | !(*forward_filter)[i]) Parent::nextOut(i); |
---|
795 | if (*static_cast<GraphEdge*>(&i)==INVALID) { |
---|
796 | Parent::firstIn(i, n); |
---|
797 | i.backward=true; |
---|
798 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
799 | !(*backward_filter)[i]) Parent::nextIn(i); |
---|
800 | } |
---|
801 | } |
---|
802 | |
---|
803 | void next(Node& i) const { |
---|
804 | Parent::next(i); |
---|
805 | } |
---|
806 | |
---|
807 | void next(Edge& i) const { |
---|
808 | if (!(i.backward)) { |
---|
809 | Parent::next(i); |
---|
810 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
811 | !(*forward_filter)[i]) Parent::next(i); |
---|
812 | if (*static_cast<GraphEdge*>(&i)==INVALID) { |
---|
813 | Parent::first(i); |
---|
814 | i.backward=true; |
---|
815 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
816 | !(*backward_filter)[i]) Parent::next(i); |
---|
817 | } |
---|
818 | } else { |
---|
819 | Parent::next(i); |
---|
820 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
821 | !(*backward_filter)[i]) Parent::next(i); |
---|
822 | } |
---|
823 | } |
---|
824 | |
---|
825 | void nextIn(Edge& i) const { |
---|
826 | if (!(i.backward)) { |
---|
827 | Node n=Parent::target(i); |
---|
828 | Parent::nextIn(i); |
---|
829 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
830 | !(*forward_filter)[i]) Parent::nextIn(i); |
---|
831 | if (*static_cast<GraphEdge*>(&i)==INVALID) { |
---|
832 | Parent::firstOut(i, n); |
---|
833 | i.backward=true; |
---|
834 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
835 | !(*backward_filter)[i]) Parent::nextOut(i); |
---|
836 | } |
---|
837 | } else { |
---|
838 | Parent::nextOut(i); |
---|
839 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
840 | !(*backward_filter)[i]) Parent::nextOut(i); |
---|
841 | } |
---|
842 | } |
---|
843 | |
---|
844 | void nextOut(Edge& i) const { |
---|
845 | if (!(i.backward)) { |
---|
846 | Node n=Parent::source(i); |
---|
847 | Parent::nextOut(i); |
---|
848 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
849 | !(*forward_filter)[i]) Parent::nextOut(i); |
---|
850 | if (*static_cast<GraphEdge*>(&i)==INVALID) { |
---|
851 | Parent::firstIn(i, n); |
---|
852 | i.backward=true; |
---|
853 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
854 | !(*backward_filter)[i]) Parent::nextIn(i); |
---|
855 | } |
---|
856 | } else { |
---|
857 | Parent::nextIn(i); |
---|
858 | while (*static_cast<GraphEdge*>(&i)!=INVALID && |
---|
859 | !(*backward_filter)[i]) Parent::nextIn(i); |
---|
860 | } |
---|
861 | } |
---|
862 | |
---|
863 | Node source(Edge e) const { |
---|
864 | return ((!e.backward) ? this->graph->source(e) : this->graph->target(e)); } |
---|
865 | Node target(Edge e) const { |
---|
866 | return ((!e.backward) ? this->graph->target(e) : this->graph->source(e)); } |
---|
867 | |
---|
868 | /// Gives back the opposite edge. |
---|
869 | Edge opposite(const Edge& e) const { |
---|
870 | Edge f=e; |
---|
871 | f.backward=!f.backward; |
---|
872 | return f; |
---|
873 | } |
---|
874 | |
---|
875 | /// \warning This is a linear time operation and works only if |
---|
876 | /// \c Graph::EdgeIt is defined. |
---|
877 | /// \todo hmm |
---|
878 | int edgeNum() const { |
---|
879 | int i=0; |
---|
880 | Edge e; |
---|
881 | for (first(e); e!=INVALID; next(e)) ++i; |
---|
882 | return i; |
---|
883 | } |
---|
884 | |
---|
885 | bool forward(const Edge& e) const { return !e.backward; } |
---|
886 | bool backward(const Edge& e) const { return e.backward; } |
---|
887 | |
---|
888 | template <typename T> |
---|
889 | /// \c SubBidirGraphWrapperBase<..., ..., ...>::EdgeMap contains two |
---|
890 | /// _Graph::EdgeMap one for the forward edges and |
---|
891 | /// one for the backward edges. |
---|
892 | class EdgeMap { |
---|
893 | template <typename TT> friend class EdgeMap; |
---|
894 | typename _Graph::template EdgeMap<T> forward_map, backward_map; |
---|
895 | public: |
---|
896 | typedef T Value; |
---|
897 | typedef Edge Key; |
---|
898 | |
---|
899 | EdgeMap(const SubBidirGraphWrapperBase<_Graph, |
---|
900 | ForwardFilterMap, BackwardFilterMap>& g) : |
---|
901 | forward_map(*(g.graph)), backward_map(*(g.graph)) { } |
---|
902 | |
---|
903 | EdgeMap(const SubBidirGraphWrapperBase<_Graph, |
---|
904 | ForwardFilterMap, BackwardFilterMap>& g, T a) : |
---|
905 | forward_map(*(g.graph), a), backward_map(*(g.graph), a) { } |
---|
906 | |
---|
907 | void set(Edge e, T a) { |
---|
908 | if (!e.backward) |
---|
909 | forward_map.set(e, a); |
---|
910 | else |
---|
911 | backward_map.set(e, a); |
---|
912 | } |
---|
913 | |
---|
914 | // typename _Graph::template EdgeMap<T>::ConstReference |
---|
915 | // operator[](Edge e) const { |
---|
916 | // if (!e.backward) |
---|
917 | // return forward_map[e]; |
---|
918 | // else |
---|
919 | // return backward_map[e]; |
---|
920 | // } |
---|
921 | |
---|
922 | // typename _Graph::template EdgeMap<T>::Reference |
---|
923 | T operator[](Edge e) const { |
---|
924 | if (!e.backward) |
---|
925 | return forward_map[e]; |
---|
926 | else |
---|
927 | return backward_map[e]; |
---|
928 | } |
---|
929 | |
---|
930 | void update() { |
---|
931 | forward_map.update(); |
---|
932 | backward_map.update(); |
---|
933 | } |
---|
934 | }; |
---|
935 | |
---|
936 | }; |
---|
937 | |
---|
938 | |
---|
939 | ///\brief A wrapper for composing a subgraph of a |
---|
940 | /// bidirected graph made from a directed one. |
---|
941 | /// |
---|
942 | /// A wrapper for composing a subgraph of a |
---|
943 | /// bidirected graph made from a directed one. |
---|
944 | /// |
---|
945 | ///\warning Graph wrappers are in even more experimental state than the other |
---|
946 | ///parts of the lib. Use them at you own risk. |
---|
947 | /// |
---|
948 | /// Let \f$G=(V, A)\f$ be a directed graph and for each directed edge |
---|
949 | /// \f$e\in A\f$, let \f$\bar e\f$ denote the edge obtained by |
---|
950 | /// reversing its orientation. We are given moreover two bool valued |
---|
951 | /// maps on the edge-set, |
---|
952 | /// \f$forward\_filter\f$, and \f$backward\_filter\f$. |
---|
953 | /// SubBidirGraphWrapper implements the graph structure with node-set |
---|
954 | /// \f$V\f$ and edge-set |
---|
955 | /// \f$\{e : e\in A \mbox{ and } forward\_filter(e) \mbox{ is true}\}+\{\bar e : e\in A \mbox{ and } backward\_filter(e) \mbox{ is true}\}\f$. |
---|
956 | /// The purpose of writing + instead of union is because parallel |
---|
957 | /// edges can arise. (Similarly, antiparallel edges also can arise). |
---|
958 | /// In other words, a subgraph of the bidirected graph obtained, which |
---|
959 | /// is given by orienting the edges of the original graph in both directions. |
---|
960 | /// As the oppositely directed edges are logically different, |
---|
961 | /// the maps are able to attach different values for them. |
---|
962 | /// |
---|
963 | /// An example for such a construction is \c RevGraphWrapper where the |
---|
964 | /// forward_filter is everywhere false and the backward_filter is |
---|
965 | /// everywhere true. We note that for sake of efficiency, |
---|
966 | /// \c RevGraphWrapper is implemented in a different way. |
---|
967 | /// But BidirGraphWrapper is obtained from |
---|
968 | /// SubBidirGraphWrapper by considering everywhere true |
---|
969 | /// valued maps both for forward_filter and backward_filter. |
---|
970 | /// Finally, one of the most important applications of SubBidirGraphWrapper |
---|
971 | /// is ResGraphWrapper, which stands for the residual graph in directed |
---|
972 | /// flow and circulation problems. |
---|
973 | /// As wrappers usually, the SubBidirGraphWrapper implements the |
---|
974 | /// above mentioned graph structure without its physical storage, |
---|
975 | /// that is the whole stuff is stored in constant memory. |
---|
976 | template<typename _Graph, |
---|
977 | typename ForwardFilterMap, typename BackwardFilterMap> |
---|
978 | class SubBidirGraphWrapper : |
---|
979 | public IterableGraphExtender< |
---|
980 | SubBidirGraphWrapperBase<_Graph, ForwardFilterMap, BackwardFilterMap> > { |
---|
981 | public: |
---|
982 | typedef _Graph Graph; |
---|
983 | typedef IterableGraphExtender< |
---|
984 | SubBidirGraphWrapperBase< |
---|
985 | _Graph, ForwardFilterMap, BackwardFilterMap> > Parent; |
---|
986 | protected: |
---|
987 | SubBidirGraphWrapper() { } |
---|
988 | public: |
---|
989 | SubBidirGraphWrapper(_Graph& _graph, ForwardFilterMap& _forward_filter, |
---|
990 | BackwardFilterMap& _backward_filter) { |
---|
991 | setGraph(_graph); |
---|
992 | setForwardFilterMap(_forward_filter); |
---|
993 | setBackwardFilterMap(_backward_filter); |
---|
994 | } |
---|
995 | }; |
---|
996 | |
---|
997 | |
---|
998 | |
---|
999 | ///\brief A wrapper for composing bidirected graph from a directed one. |
---|
1000 | /// |
---|
1001 | ///\warning Graph wrappers are in even more experimental state than the other |
---|
1002 | ///parts of the lib. Use them at you own risk. |
---|
1003 | /// |
---|
1004 | /// A wrapper for composing bidirected graph from a directed one. |
---|
1005 | /// A bidirected graph is composed over the directed one without physical |
---|
1006 | /// storage. As the oppositely directed edges are logically different ones |
---|
1007 | /// the maps are able to attach different values for them. |
---|
1008 | template<typename Graph> |
---|
1009 | class BidirGraphWrapper : |
---|
1010 | public SubBidirGraphWrapper< |
---|
1011 | Graph, |
---|
1012 | ConstMap<typename Graph::Edge, bool>, |
---|
1013 | ConstMap<typename Graph::Edge, bool> > { |
---|
1014 | public: |
---|
1015 | typedef SubBidirGraphWrapper< |
---|
1016 | Graph, |
---|
1017 | ConstMap<typename Graph::Edge, bool>, |
---|
1018 | ConstMap<typename Graph::Edge, bool> > Parent; |
---|
1019 | protected: |
---|
1020 | ConstMap<typename Graph::Edge, bool> cm; |
---|
1021 | |
---|
1022 | BidirGraphWrapper() : Parent(), cm(true) { |
---|
1023 | Parent::setForwardFilterMap(cm); |
---|
1024 | Parent::setBackwardFilterMap(cm); |
---|
1025 | } |
---|
1026 | public: |
---|
1027 | BidirGraphWrapper(Graph& _graph) : Parent() { |
---|
1028 | Parent::setGraph(_graph); |
---|
1029 | Parent::setForwardFilterMap(cm); |
---|
1030 | Parent::setBackwardFilterMap(cm); |
---|
1031 | } |
---|
1032 | |
---|
1033 | int edgeNum() const { |
---|
1034 | return 2*this->graph->edgeNum(); |
---|
1035 | } |
---|
1036 | // KEEP_MAPS(Parent, BidirGraphWrapper); |
---|
1037 | }; |
---|
1038 | |
---|
1039 | |
---|
1040 | template<typename Graph, typename Number, |
---|
1041 | typename CapacityMap, typename FlowMap> |
---|
1042 | class ResForwardFilter { |
---|
1043 | // const Graph* graph; |
---|
1044 | const CapacityMap* capacity; |
---|
1045 | const FlowMap* flow; |
---|
1046 | public: |
---|
1047 | ResForwardFilter(/*const Graph& _graph, */ |
---|
1048 | const CapacityMap& _capacity, const FlowMap& _flow) : |
---|
1049 | /*graph(&_graph),*/ capacity(&_capacity), flow(&_flow) { } |
---|
1050 | ResForwardFilter() : /*graph(0),*/ capacity(0), flow(0) { } |
---|
1051 | void setCapacity(const CapacityMap& _capacity) { capacity=&_capacity; } |
---|
1052 | void setFlow(const FlowMap& _flow) { flow=&_flow; } |
---|
1053 | bool operator[](const typename Graph::Edge& e) const { |
---|
1054 | return (Number((*flow)[e]) < Number((*capacity)[e])); |
---|
1055 | } |
---|
1056 | }; |
---|
1057 | |
---|
1058 | template<typename Graph, typename Number, |
---|
1059 | typename CapacityMap, typename FlowMap> |
---|
1060 | class ResBackwardFilter { |
---|
1061 | const CapacityMap* capacity; |
---|
1062 | const FlowMap* flow; |
---|
1063 | public: |
---|
1064 | ResBackwardFilter(/*const Graph& _graph,*/ |
---|
1065 | const CapacityMap& _capacity, const FlowMap& _flow) : |
---|
1066 | /*graph(&_graph),*/ capacity(&_capacity), flow(&_flow) { } |
---|
1067 | ResBackwardFilter() : /*graph(0),*/ capacity(0), flow(0) { } |
---|
1068 | void setCapacity(const CapacityMap& _capacity) { capacity=&_capacity; } |
---|
1069 | void setFlow(const FlowMap& _flow) { flow=&_flow; } |
---|
1070 | bool operator[](const typename Graph::Edge& e) const { |
---|
1071 | return (Number(0) < Number((*flow)[e])); |
---|
1072 | } |
---|
1073 | }; |
---|
1074 | |
---|
1075 | |
---|
1076 | /// A wrapper for composing the residual graph for directed flow and circulation problems. |
---|
1077 | |
---|
1078 | ///\warning Graph wrappers are in even more experimental state than the other |
---|
1079 | ///parts of the lib. Use them at you own risk. |
---|
1080 | /// |
---|
1081 | /// A wrapper for composing the residual graph for directed flow and circulation problems. |
---|
1082 | template<typename Graph, typename Number, |
---|
1083 | typename CapacityMap, typename FlowMap> |
---|
1084 | class ResGraphWrapper : |
---|
1085 | public SubBidirGraphWrapper< |
---|
1086 | Graph, |
---|
1087 | ResForwardFilter<Graph, Number, CapacityMap, FlowMap>, |
---|
1088 | ResBackwardFilter<Graph, Number, CapacityMap, FlowMap> > { |
---|
1089 | public: |
---|
1090 | typedef SubBidirGraphWrapper< |
---|
1091 | Graph, |
---|
1092 | ResForwardFilter<Graph, Number, CapacityMap, FlowMap>, |
---|
1093 | ResBackwardFilter<Graph, Number, CapacityMap, FlowMap> > Parent; |
---|
1094 | protected: |
---|
1095 | const CapacityMap* capacity; |
---|
1096 | FlowMap* flow; |
---|
1097 | ResForwardFilter<Graph, Number, CapacityMap, FlowMap> forward_filter; |
---|
1098 | ResBackwardFilter<Graph, Number, CapacityMap, FlowMap> backward_filter; |
---|
1099 | ResGraphWrapper() : Parent(), |
---|
1100 | capacity(0), flow(0) { } |
---|
1101 | void setCapacityMap(const CapacityMap& _capacity) { |
---|
1102 | capacity=&_capacity; |
---|
1103 | forward_filter.setCapacity(_capacity); |
---|
1104 | backward_filter.setCapacity(_capacity); |
---|
1105 | } |
---|
1106 | void setFlowMap(FlowMap& _flow) { |
---|
1107 | flow=&_flow; |
---|
1108 | forward_filter.setFlow(_flow); |
---|
1109 | backward_filter.setFlow(_flow); |
---|
1110 | } |
---|
1111 | public: |
---|
1112 | ResGraphWrapper(Graph& _graph, const CapacityMap& _capacity, |
---|
1113 | FlowMap& _flow) : |
---|
1114 | Parent(), capacity(&_capacity), flow(&_flow), |
---|
1115 | forward_filter(/*_graph,*/ _capacity, _flow), |
---|
1116 | backward_filter(/*_graph,*/ _capacity, _flow) { |
---|
1117 | Parent::setGraph(_graph); |
---|
1118 | Parent::setForwardFilterMap(forward_filter); |
---|
1119 | Parent::setBackwardFilterMap(backward_filter); |
---|
1120 | } |
---|
1121 | |
---|
1122 | typedef typename Parent::Edge Edge; |
---|
1123 | |
---|
1124 | void augment(const Edge& e, Number a) const { |
---|
1125 | if (Parent::forward(e)) |
---|
1126 | flow->set(e, (*flow)[e]+a); |
---|
1127 | else |
---|
1128 | flow->set(e, (*flow)[e]-a); |
---|
1129 | } |
---|
1130 | |
---|
1131 | /// \brief Residual capacity map. |
---|
1132 | /// |
---|
1133 | /// In generic residual graphs the residual capacity can be obtained |
---|
1134 | /// as a map. |
---|
1135 | class ResCap { |
---|
1136 | protected: |
---|
1137 | const ResGraphWrapper<Graph, Number, CapacityMap, FlowMap>* res_graph; |
---|
1138 | public: |
---|
1139 | typedef Number Value; |
---|
1140 | typedef Edge Key; |
---|
1141 | ResCap(const ResGraphWrapper<Graph, Number, CapacityMap, FlowMap>& |
---|
1142 | _res_graph) : res_graph(&_res_graph) { } |
---|
1143 | Number operator[](const Edge& e) const { |
---|
1144 | if (res_graph->forward(e)) |
---|
1145 | return (*(res_graph->capacity))[e]-(*(res_graph->flow))[e]; |
---|
1146 | else |
---|
1147 | return (*(res_graph->flow))[e]; |
---|
1148 | } |
---|
1149 | }; |
---|
1150 | |
---|
1151 | // KEEP_MAPS(Parent, ResGraphWrapper); |
---|
1152 | }; |
---|
1153 | |
---|
1154 | |
---|
1155 | |
---|
1156 | template <typename _Graph, typename FirstOutEdgesMap> |
---|
1157 | class ErasingFirstGraphWrapperBase : public GraphWrapperBase<_Graph> { |
---|
1158 | public: |
---|
1159 | typedef _Graph Graph; |
---|
1160 | typedef GraphWrapperBase<_Graph> Parent; |
---|
1161 | protected: |
---|
1162 | FirstOutEdgesMap* first_out_edges; |
---|
1163 | ErasingFirstGraphWrapperBase() : Parent(), |
---|
1164 | first_out_edges(0) { } |
---|
1165 | |
---|
1166 | void setFirstOutEdgesMap(FirstOutEdgesMap& _first_out_edges) { |
---|
1167 | first_out_edges=&_first_out_edges; |
---|
1168 | } |
---|
1169 | |
---|
1170 | public: |
---|
1171 | |
---|
1172 | typedef typename Parent::Node Node; |
---|
1173 | typedef typename Parent::Edge Edge; |
---|
1174 | |
---|
1175 | void firstOut(Edge& i, const Node& n) const { |
---|
1176 | i=(*first_out_edges)[n]; |
---|
1177 | } |
---|
1178 | |
---|
1179 | void erase(const Edge& e) const { |
---|
1180 | Node n=source(e); |
---|
1181 | Edge f=e; |
---|
1182 | Parent::nextOut(f); |
---|
1183 | first_out_edges->set(n, f); |
---|
1184 | } |
---|
1185 | }; |
---|
1186 | |
---|
1187 | |
---|
1188 | /// For blocking flows. |
---|
1189 | |
---|
1190 | ///\warning Graph wrappers are in even more experimental state than the other |
---|
1191 | ///parts of the lib. Use them at you own risk. |
---|
1192 | /// |
---|
1193 | /// This graph wrapper is used for on-the-fly |
---|
1194 | /// Dinits blocking flow computations. |
---|
1195 | /// For each node, an out-edge is stored which is used when the |
---|
1196 | /// \code |
---|
1197 | /// OutEdgeIt& first(OutEdgeIt&, const Node&) |
---|
1198 | /// \endcode |
---|
1199 | /// is called. |
---|
1200 | /// |
---|
1201 | /// \author Marton Makai |
---|
1202 | template <typename _Graph, typename FirstOutEdgesMap> |
---|
1203 | class ErasingFirstGraphWrapper : |
---|
1204 | public IterableGraphExtender< |
---|
1205 | ErasingFirstGraphWrapperBase<_Graph, FirstOutEdgesMap> > { |
---|
1206 | public: |
---|
1207 | typedef _Graph Graph; |
---|
1208 | typedef IterableGraphExtender< |
---|
1209 | ErasingFirstGraphWrapperBase<_Graph, FirstOutEdgesMap> > Parent; |
---|
1210 | ErasingFirstGraphWrapper(Graph& _graph, |
---|
1211 | FirstOutEdgesMap& _first_out_edges) { |
---|
1212 | setGraph(_graph); |
---|
1213 | setFirstOutEdgesMap(_first_out_edges); |
---|
1214 | } |
---|
1215 | |
---|
1216 | }; |
---|
1217 | |
---|
1218 | ///@} |
---|
1219 | |
---|
1220 | } //namespace lemon |
---|
1221 | |
---|
1222 | #endif //LEMON_GRAPH_WRAPPER_H |
---|
1223 | |
---|