1 | /* -*- C++ -*- |
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2 | * |
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3 | * This file is a part of LEMON, a generic C++ optimization library |
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4 | * |
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5 | * Copyright (C) 2003-2010 |
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6 | * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
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7 | * (Egervary Research Group on Combinatorial Optimization, EGRES). |
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8 | * |
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9 | * Permission to use, modify and distribute this software is granted |
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10 | * provided that this copyright notice appears in all copies. For |
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11 | * precise terms see the accompanying LICENSE file. |
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12 | * |
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13 | * This software is provided "AS IS" with no warranty of any kind, |
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14 | * express or implied, and with no claim as to its suitability for any |
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15 | * purpose. |
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16 | * |
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17 | */ |
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18 | |
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19 | #ifndef LEMON_MAX_CARDINALITY_SEARCH_H |
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20 | #define LEMON_MAX_CARDINALITY_SEARCH_H |
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21 | |
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22 | |
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23 | /// \ingroup search |
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24 | /// \file |
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25 | /// \brief Maximum cardinality search in undirected digraphs. |
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26 | |
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27 | #include <lemon/bin_heap.h> |
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28 | #include <lemon/bucket_heap.h> |
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29 | |
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30 | #include <lemon/error.h> |
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31 | #include <lemon/maps.h> |
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32 | |
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33 | #include <functional> |
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34 | |
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35 | namespace lemon { |
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36 | |
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37 | /// \brief Default traits class of MaxCardinalitySearch class. |
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38 | /// |
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39 | /// Default traits class of MaxCardinalitySearch class. |
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40 | /// \param Digraph Digraph type. |
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41 | /// \param CapacityMap Type of capacity map. |
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42 | template <typename GR, typename CAP> |
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43 | struct MaxCardinalitySearchDefaultTraits { |
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44 | /// The digraph type the algorithm runs on. |
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45 | typedef GR Digraph; |
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46 | |
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47 | template <typename CM> |
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48 | struct CapMapSelector { |
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49 | |
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50 | typedef CM CapacityMap; |
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51 | |
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52 | static CapacityMap *createCapacityMap(const Digraph& g) { |
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53 | return new CapacityMap(g); |
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54 | } |
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55 | }; |
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56 | |
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57 | template <typename CM> |
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58 | struct CapMapSelector<ConstMap<CM, Const<int, 1> > > { |
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59 | |
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60 | typedef ConstMap<CM, Const<int, 1> > CapacityMap; |
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61 | |
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62 | static CapacityMap *createCapacityMap(const Digraph&) { |
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63 | return new CapacityMap; |
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64 | } |
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65 | }; |
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66 | |
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67 | /// \brief The type of the map that stores the arc capacities. |
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68 | /// |
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69 | /// The type of the map that stores the arc capacities. |
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70 | /// It must meet the \ref concepts::ReadMap "ReadMap" concept. |
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71 | typedef typename CapMapSelector<CAP>::CapacityMap CapacityMap; |
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72 | |
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73 | /// \brief The type of the capacity of the arcs. |
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74 | typedef typename CapacityMap::Value Value; |
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75 | |
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76 | /// \brief Instantiates a CapacityMap. |
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77 | /// |
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78 | /// This function instantiates a \ref CapacityMap. |
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79 | /// \param digraph is the digraph, to which we would like to define |
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80 | /// the CapacityMap. |
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81 | static CapacityMap *createCapacityMap(const Digraph& digraph) { |
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82 | return CapMapSelector<CapacityMap>::createCapacityMap(digraph); |
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83 | } |
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84 | |
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85 | /// \brief The cross reference type used by heap. |
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86 | /// |
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87 | /// The cross reference type used by heap. |
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88 | /// Usually it is \c Digraph::NodeMap<int>. |
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89 | typedef typename Digraph::template NodeMap<int> HeapCrossRef; |
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90 | |
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91 | /// \brief Instantiates a HeapCrossRef. |
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92 | /// |
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93 | /// This function instantiates a \ref HeapCrossRef. |
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94 | /// \param digraph is the digraph, to which we would like to define the |
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95 | /// HeapCrossRef. |
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96 | static HeapCrossRef *createHeapCrossRef(const Digraph &digraph) { |
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97 | return new HeapCrossRef(digraph); |
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98 | } |
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99 | |
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100 | template <typename CapacityMap> |
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101 | struct HeapSelector { |
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102 | template <typename Value, typename Ref> |
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103 | struct Selector { |
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104 | typedef BinHeap<Value, Ref, std::greater<Value> > Heap; |
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105 | }; |
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106 | }; |
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107 | |
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108 | template <typename CapacityKey> |
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109 | struct HeapSelector<ConstMap<CapacityKey, Const<int, 1> > > { |
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110 | template <typename Value, typename Ref> |
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111 | struct Selector { |
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112 | typedef BucketHeap<Ref, false > Heap; |
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113 | }; |
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114 | }; |
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115 | |
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116 | /// \brief The heap type used by MaxCardinalitySearch algorithm. |
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117 | /// |
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118 | /// The heap type used by MaxCardinalitySearch algorithm. It should |
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119 | /// maximalize the priorities. The default heap type is |
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120 | /// the \ref BinHeap, but it is specialized when the |
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121 | /// CapacityMap is ConstMap<Digraph::Node, Const<int, 1> > |
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122 | /// to BucketHeap. |
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123 | /// |
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124 | /// \sa MaxCardinalitySearch |
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125 | typedef typename HeapSelector<CapacityMap> |
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126 | ::template Selector<Value, HeapCrossRef> |
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127 | ::Heap Heap; |
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128 | |
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129 | /// \brief Instantiates a Heap. |
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130 | /// |
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131 | /// This function instantiates a \ref Heap. |
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132 | /// \param crossref The cross reference of the heap. |
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133 | static Heap *createHeap(HeapCrossRef& crossref) { |
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134 | return new Heap(crossref); |
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135 | } |
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136 | |
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137 | /// \brief The type of the map that stores whether a node is processed. |
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138 | /// |
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139 | /// The type of the map that stores whether a node is processed. |
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140 | /// It must meet the \ref concepts::WriteMap "WriteMap" concept. |
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141 | /// By default it is a NullMap. |
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142 | typedef NullMap<typename Digraph::Node, bool> ProcessedMap; |
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143 | |
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144 | /// \brief Instantiates a ProcessedMap. |
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145 | /// |
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146 | /// This function instantiates a \ref ProcessedMap. |
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147 | /// \param digraph is the digraph, to which |
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148 | /// we would like to define the \ref ProcessedMap |
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149 | #ifdef DOXYGEN |
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150 | static ProcessedMap *createProcessedMap(const Digraph &digraph) |
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151 | #else |
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152 | static ProcessedMap *createProcessedMap(const Digraph &) |
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153 | #endif |
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154 | { |
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155 | return new ProcessedMap(); |
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156 | } |
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157 | |
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158 | /// \brief The type of the map that stores the cardinalities of the nodes. |
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159 | /// |
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160 | /// The type of the map that stores the cardinalities of the nodes. |
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161 | /// It must meet the \ref concepts::WriteMap "WriteMap" concept. |
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162 | typedef typename Digraph::template NodeMap<Value> CardinalityMap; |
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163 | |
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164 | /// \brief Instantiates a CardinalityMap. |
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165 | /// |
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166 | /// This function instantiates a \ref CardinalityMap. |
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167 | /// \param digraph is the digraph, to which we would like to define the \ref |
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168 | /// CardinalityMap |
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169 | static CardinalityMap *createCardinalityMap(const Digraph &digraph) { |
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170 | return new CardinalityMap(digraph); |
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171 | } |
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172 | |
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173 | |
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174 | }; |
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175 | |
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176 | /// \ingroup search |
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177 | /// |
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178 | /// \brief Maximum Cardinality Search algorithm class. |
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179 | /// |
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180 | /// This class provides an efficient implementation of Maximum Cardinality |
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181 | /// Search algorithm. The maximum cardinality search first chooses any |
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182 | /// node of the digraph. Then every time it chooses one unprocessed node |
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183 | /// with maximum cardinality, i.e the sum of capacities on out arcs to the nodes |
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184 | /// which were previusly processed. |
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185 | /// If there is a cut in the digraph the algorithm should choose |
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186 | /// again any unprocessed node of the digraph. |
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187 | |
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188 | /// The arc capacities are passed to the algorithm using a |
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189 | /// \ref concepts::ReadMap "ReadMap", so it is easy to change it to any |
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190 | /// kind of capacity. |
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191 | /// |
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192 | /// The type of the capacity is determined by the \ref |
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193 | /// concepts::ReadMap::Value "Value" of the capacity map. |
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194 | /// |
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195 | /// It is also possible to change the underlying priority heap. |
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196 | /// |
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197 | /// |
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198 | /// \param GR The digraph type the algorithm runs on. The value of |
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199 | /// Digraph is not used directly by the search algorithm, it |
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200 | /// is only passed to \ref MaxCardinalitySearchDefaultTraits. |
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201 | /// \param CAP This read-only ArcMap determines the capacities of |
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202 | /// the arcs. It is read once for each arc, so the map may involve in |
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203 | /// relatively time consuming process to compute the arc capacity if |
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204 | /// it is necessary. The default map type is \ref |
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205 | /// ConstMap "ConstMap<concepts::Digraph::Arc, Const<int,1> >". The value |
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206 | /// of CapacityMap is not used directly by search algorithm, it is only |
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207 | /// passed to \ref MaxCardinalitySearchDefaultTraits. |
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208 | /// \param TR Traits class to set various data types used by the |
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209 | /// algorithm. The default traits class is |
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210 | /// \ref MaxCardinalitySearchDefaultTraits |
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211 | /// "MaxCardinalitySearchDefaultTraits<GR, CAP>". |
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212 | /// See \ref MaxCardinalitySearchDefaultTraits |
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213 | /// for the documentation of a MaxCardinalitySearch traits class. |
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214 | |
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215 | #ifdef DOXYGEN |
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216 | template <typename GR, typename CAP, typename TR> |
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217 | #else |
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218 | template <typename GR, typename CAP = |
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219 | ConstMap<typename GR::Arc, Const<int,1> >, |
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220 | typename TR = |
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221 | MaxCardinalitySearchDefaultTraits<GR, CAP> > |
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222 | #endif |
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223 | class MaxCardinalitySearch { |
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224 | public: |
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225 | |
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226 | typedef TR Traits; |
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227 | ///The type of the underlying digraph. |
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228 | typedef typename Traits::Digraph Digraph; |
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229 | |
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230 | ///The type of the capacity of the arcs. |
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231 | typedef typename Traits::CapacityMap::Value Value; |
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232 | ///The type of the map that stores the arc capacities. |
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233 | typedef typename Traits::CapacityMap CapacityMap; |
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234 | ///The type of the map indicating if a node is processed. |
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235 | typedef typename Traits::ProcessedMap ProcessedMap; |
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236 | ///The type of the map that stores the cardinalities of the nodes. |
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237 | typedef typename Traits::CardinalityMap CardinalityMap; |
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238 | ///The cross reference type used for the current heap. |
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239 | typedef typename Traits::HeapCrossRef HeapCrossRef; |
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240 | ///The heap type used by the algorithm. It maximizes the priorities. |
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241 | typedef typename Traits::Heap Heap; |
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242 | private: |
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243 | // Pointer to the underlying digraph. |
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244 | const Digraph *_graph; |
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245 | // Pointer to the capacity map |
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246 | const CapacityMap *_capacity; |
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247 | // Indicates if \ref _capacity is locally allocated (\c true) or not. |
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248 | bool local_capacity; |
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249 | // Pointer to the map of cardinality. |
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250 | CardinalityMap *_cardinality; |
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251 | // Indicates if \ref _cardinality is locally allocated (\c true) or not. |
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252 | bool local_cardinality; |
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253 | // Pointer to the map of processed status of the nodes. |
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254 | ProcessedMap *_processed; |
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255 | // Indicates if \ref _processed is locally allocated (\c true) or not. |
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256 | bool local_processed; |
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257 | // Pointer to the heap cross references. |
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258 | HeapCrossRef *_heap_cross_ref; |
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259 | // Indicates if \ref _heap_cross_ref is locally allocated (\c true) or not. |
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260 | bool local_heap_cross_ref; |
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261 | // Pointer to the heap. |
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262 | Heap *_heap; |
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263 | // Indicates if \ref _heap is locally allocated (\c true) or not. |
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264 | bool local_heap; |
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265 | |
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266 | public : |
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267 | |
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268 | typedef MaxCardinalitySearch Create; |
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269 | |
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270 | ///\name Named template parameters |
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271 | |
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272 | ///@{ |
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273 | |
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274 | template <class T> |
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275 | struct DefCapacityMapTraits : public Traits { |
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276 | typedef T CapacityMap; |
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277 | static CapacityMap *createCapacityMap(const Digraph &) { |
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278 | LEMON_ASSERT(false,"Uninitialized parameter."); |
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279 | return 0; |
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280 | } |
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281 | }; |
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282 | /// \brief \ref named-templ-param "Named parameter" for setting |
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283 | /// CapacityMap type |
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284 | /// |
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285 | /// \ref named-templ-param "Named parameter" for setting CapacityMap type |
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286 | /// for the algorithm. |
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287 | template <class T> |
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288 | struct SetCapacityMap |
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289 | : public MaxCardinalitySearch<Digraph, CapacityMap, |
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290 | DefCapacityMapTraits<T> > { |
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291 | typedef MaxCardinalitySearch<Digraph, CapacityMap, |
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292 | DefCapacityMapTraits<T> > Create; |
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293 | }; |
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294 | |
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295 | template <class T> |
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296 | struct DefCardinalityMapTraits : public Traits { |
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297 | typedef T CardinalityMap; |
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298 | static CardinalityMap *createCardinalityMap(const Digraph &) |
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299 | { |
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300 | LEMON_ASSERT(false,"Uninitialized parameter."); |
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301 | return 0; |
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302 | } |
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303 | }; |
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304 | /// \brief \ref named-templ-param "Named parameter" for setting |
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305 | /// CardinalityMap type |
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306 | /// |
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307 | /// \ref named-templ-param "Named parameter" for setting CardinalityMap |
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308 | /// type for the algorithm. |
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309 | template <class T> |
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310 | struct SetCardinalityMap |
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311 | : public MaxCardinalitySearch<Digraph, CapacityMap, |
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312 | DefCardinalityMapTraits<T> > { |
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313 | typedef MaxCardinalitySearch<Digraph, CapacityMap, |
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314 | DefCardinalityMapTraits<T> > Create; |
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315 | }; |
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316 | |
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317 | template <class T> |
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318 | struct DefProcessedMapTraits : public Traits { |
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319 | typedef T ProcessedMap; |
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320 | static ProcessedMap *createProcessedMap(const Digraph &) { |
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321 | LEMON_ASSERT(false,"Uninitialized parameter."); |
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322 | return 0; |
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323 | } |
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324 | }; |
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325 | /// \brief \ref named-templ-param "Named parameter" for setting |
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326 | /// ProcessedMap type |
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327 | /// |
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328 | /// \ref named-templ-param "Named parameter" for setting ProcessedMap type |
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329 | /// for the algorithm. |
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330 | template <class T> |
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331 | struct SetProcessedMap |
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332 | : public MaxCardinalitySearch<Digraph, CapacityMap, |
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333 | DefProcessedMapTraits<T> > { |
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334 | typedef MaxCardinalitySearch<Digraph, CapacityMap, |
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335 | DefProcessedMapTraits<T> > Create; |
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336 | }; |
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337 | |
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338 | template <class H, class CR> |
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339 | struct DefHeapTraits : public Traits { |
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340 | typedef CR HeapCrossRef; |
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341 | typedef H Heap; |
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342 | static HeapCrossRef *createHeapCrossRef(const Digraph &) { |
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343 | LEMON_ASSERT(false,"Uninitialized parameter."); |
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344 | return 0; |
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345 | } |
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346 | static Heap *createHeap(HeapCrossRef &) { |
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347 | LEMON_ASSERT(false,"Uninitialized parameter."); |
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348 | return 0; |
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349 | } |
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350 | }; |
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351 | /// \brief \ref named-templ-param "Named parameter" for setting heap |
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352 | /// and cross reference type |
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353 | /// |
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354 | /// \ref named-templ-param "Named parameter" for setting heap and cross |
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355 | /// reference type for the algorithm. |
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356 | template <class H, class CR = typename Digraph::template NodeMap<int> > |
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357 | struct SetHeap |
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358 | : public MaxCardinalitySearch<Digraph, CapacityMap, |
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359 | DefHeapTraits<H, CR> > { |
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360 | typedef MaxCardinalitySearch< Digraph, CapacityMap, |
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361 | DefHeapTraits<H, CR> > Create; |
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362 | }; |
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363 | |
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364 | template <class H, class CR> |
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365 | struct DefStandardHeapTraits : public Traits { |
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366 | typedef CR HeapCrossRef; |
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367 | typedef H Heap; |
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368 | static HeapCrossRef *createHeapCrossRef(const Digraph &digraph) { |
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369 | return new HeapCrossRef(digraph); |
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370 | } |
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371 | static Heap *createHeap(HeapCrossRef &crossref) { |
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372 | return new Heap(crossref); |
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373 | } |
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374 | }; |
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375 | |
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376 | /// \brief \ref named-templ-param "Named parameter" for setting heap and |
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377 | /// cross reference type with automatic allocation |
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378 | /// |
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379 | /// \ref named-templ-param "Named parameter" for setting heap and cross |
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380 | /// reference type. It can allocate the heap and the cross reference |
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381 | /// object if the cross reference's constructor waits for the digraph as |
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382 | /// parameter and the heap's constructor waits for the cross reference. |
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383 | template <class H, class CR = typename Digraph::template NodeMap<int> > |
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384 | struct SetStandardHeap |
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385 | : public MaxCardinalitySearch<Digraph, CapacityMap, |
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386 | DefStandardHeapTraits<H, CR> > { |
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387 | typedef MaxCardinalitySearch<Digraph, CapacityMap, |
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388 | DefStandardHeapTraits<H, CR> > |
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389 | Create; |
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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 | protected: |
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396 | |
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397 | MaxCardinalitySearch() {} |
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398 | |
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399 | public: |
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400 | |
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401 | /// \brief Constructor. |
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402 | /// |
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403 | ///\param digraph the digraph the algorithm will run on. |
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404 | ///\param capacity the capacity map used by the algorithm. |
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405 | MaxCardinalitySearch(const Digraph& digraph, |
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406 | const CapacityMap& capacity) : |
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407 | _graph(&digraph), |
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408 | _capacity(&capacity), local_capacity(false), |
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409 | _cardinality(0), local_cardinality(false), |
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410 | _processed(0), local_processed(false), |
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411 | _heap_cross_ref(0), local_heap_cross_ref(false), |
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412 | _heap(0), local_heap(false) |
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413 | { } |
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414 | |
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415 | /// \brief Constructor. |
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416 | /// |
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417 | ///\param digraph the digraph the algorithm will run on. |
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418 | /// |
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419 | ///A constant 1 capacity map will be allocated. |
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420 | MaxCardinalitySearch(const Digraph& digraph) : |
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421 | _graph(&digraph), |
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422 | _capacity(0), local_capacity(false), |
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423 | _cardinality(0), local_cardinality(false), |
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424 | _processed(0), local_processed(false), |
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425 | _heap_cross_ref(0), local_heap_cross_ref(false), |
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426 | _heap(0), local_heap(false) |
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427 | { } |
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428 | |
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429 | /// \brief Destructor. |
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430 | ~MaxCardinalitySearch() { |
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431 | if(local_capacity) delete _capacity; |
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432 | if(local_cardinality) delete _cardinality; |
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433 | if(local_processed) delete _processed; |
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434 | if(local_heap_cross_ref) delete _heap_cross_ref; |
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435 | if(local_heap) delete _heap; |
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436 | } |
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437 | |
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438 | /// \brief Sets the capacity map. |
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439 | /// |
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440 | /// Sets the capacity map. |
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441 | /// \return <tt> (*this) </tt> |
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442 | MaxCardinalitySearch &capacityMap(const CapacityMap &m) { |
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443 | if (local_capacity) { |
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444 | delete _capacity; |
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445 | local_capacity=false; |
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446 | } |
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447 | _capacity=&m; |
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448 | return *this; |
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449 | } |
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450 | |
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451 | /// \brief Returns a const reference to the capacity map. |
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452 | /// |
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453 | /// Returns a const reference to the capacity map used by |
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454 | /// the algorithm. |
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455 | const CapacityMap &capacityMap() const { |
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456 | return *_capacity; |
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457 | } |
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458 | |
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459 | /// \brief Sets the map storing the cardinalities calculated by the |
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460 | /// algorithm. |
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461 | /// |
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462 | /// Sets the map storing the cardinalities calculated by the algorithm. |
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463 | /// If you don't use this function before calling \ref run(), |
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464 | /// it will allocate one. The destuctor deallocates this |
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465 | /// automatically allocated map, of course. |
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466 | /// \return <tt> (*this) </tt> |
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467 | MaxCardinalitySearch &cardinalityMap(CardinalityMap &m) { |
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468 | if(local_cardinality) { |
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469 | delete _cardinality; |
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470 | local_cardinality=false; |
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471 | } |
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472 | _cardinality = &m; |
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473 | return *this; |
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474 | } |
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475 | |
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476 | /// \brief Sets the map storing the processed nodes. |
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477 | /// |
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478 | /// Sets the map storing the processed nodes. |
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479 | /// If you don't use this function before calling \ref run(), |
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480 | /// it will allocate one. The destuctor deallocates this |
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481 | /// automatically allocated map, of course. |
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482 | /// \return <tt> (*this) </tt> |
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483 | MaxCardinalitySearch &processedMap(ProcessedMap &m) |
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484 | { |
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485 | if(local_processed) { |
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486 | delete _processed; |
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487 | local_processed=false; |
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488 | } |
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489 | _processed = &m; |
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490 | return *this; |
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491 | } |
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492 | |
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493 | /// \brief Returns a const reference to the cardinality map. |
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494 | /// |
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495 | /// Returns a const reference to the cardinality map used by |
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496 | /// the algorithm. |
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497 | const ProcessedMap &processedMap() const { |
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498 | return *_processed; |
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499 | } |
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500 | |
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501 | /// \brief Sets the heap and the cross reference used by algorithm. |
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502 | /// |
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503 | /// Sets the heap and the cross reference used by algorithm. |
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504 | /// If you don't use this function before calling \ref run(), |
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505 | /// it will allocate one. The destuctor deallocates this |
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506 | /// automatically allocated map, of course. |
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507 | /// \return <tt> (*this) </tt> |
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508 | MaxCardinalitySearch &heap(Heap& hp, HeapCrossRef &cr) { |
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509 | if(local_heap_cross_ref) { |
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510 | delete _heap_cross_ref; |
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511 | local_heap_cross_ref = false; |
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512 | } |
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513 | _heap_cross_ref = &cr; |
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514 | if(local_heap) { |
---|
515 | delete _heap; |
---|
516 | local_heap = false; |
---|
517 | } |
---|
518 | _heap = &hp; |
---|
519 | return *this; |
---|
520 | } |
---|
521 | |
---|
522 | /// \brief Returns a const reference to the heap. |
---|
523 | /// |
---|
524 | /// Returns a const reference to the heap used by |
---|
525 | /// the algorithm. |
---|
526 | const Heap &heap() const { |
---|
527 | return *_heap; |
---|
528 | } |
---|
529 | |
---|
530 | /// \brief Returns a const reference to the cross reference. |
---|
531 | /// |
---|
532 | /// Returns a const reference to the cross reference |
---|
533 | /// of the heap. |
---|
534 | const HeapCrossRef &heapCrossRef() const { |
---|
535 | return *_heap_cross_ref; |
---|
536 | } |
---|
537 | |
---|
538 | private: |
---|
539 | |
---|
540 | typedef typename Digraph::Node Node; |
---|
541 | typedef typename Digraph::NodeIt NodeIt; |
---|
542 | typedef typename Digraph::Arc Arc; |
---|
543 | typedef typename Digraph::InArcIt InArcIt; |
---|
544 | |
---|
545 | void create_maps() { |
---|
546 | if(!_capacity) { |
---|
547 | local_capacity = true; |
---|
548 | _capacity = Traits::createCapacityMap(*_graph); |
---|
549 | } |
---|
550 | if(!_cardinality) { |
---|
551 | local_cardinality = true; |
---|
552 | _cardinality = Traits::createCardinalityMap(*_graph); |
---|
553 | } |
---|
554 | if(!_processed) { |
---|
555 | local_processed = true; |
---|
556 | _processed = Traits::createProcessedMap(*_graph); |
---|
557 | } |
---|
558 | if (!_heap_cross_ref) { |
---|
559 | local_heap_cross_ref = true; |
---|
560 | _heap_cross_ref = Traits::createHeapCrossRef(*_graph); |
---|
561 | } |
---|
562 | if (!_heap) { |
---|
563 | local_heap = true; |
---|
564 | _heap = Traits::createHeap(*_heap_cross_ref); |
---|
565 | } |
---|
566 | } |
---|
567 | |
---|
568 | void finalizeNodeData(Node node, Value capacity) { |
---|
569 | _processed->set(node, true); |
---|
570 | _cardinality->set(node, capacity); |
---|
571 | } |
---|
572 | |
---|
573 | public: |
---|
574 | /// \name Execution control |
---|
575 | /// The simplest way to execute the algorithm is to use |
---|
576 | /// one of the member functions called \ref run(). |
---|
577 | /// \n |
---|
578 | /// If you need more control on the execution, |
---|
579 | /// first you must call \ref init(), then you can add several source nodes |
---|
580 | /// with \ref addSource(). |
---|
581 | /// Finally \ref start() will perform the computation. |
---|
582 | |
---|
583 | ///@{ |
---|
584 | |
---|
585 | /// \brief Initializes the internal data structures. |
---|
586 | /// |
---|
587 | /// Initializes the internal data structures, and clears the heap. |
---|
588 | void init() { |
---|
589 | create_maps(); |
---|
590 | _heap->clear(); |
---|
591 | for (NodeIt it(*_graph) ; it != INVALID ; ++it) { |
---|
592 | _processed->set(it, false); |
---|
593 | _heap_cross_ref->set(it, Heap::PRE_HEAP); |
---|
594 | } |
---|
595 | } |
---|
596 | |
---|
597 | /// \brief Adds a new source node. |
---|
598 | /// |
---|
599 | /// Adds a new source node to the priority heap. |
---|
600 | /// |
---|
601 | /// It checks if the node has not yet been added to the heap. |
---|
602 | void addSource(Node source, Value capacity = 0) { |
---|
603 | if(_heap->state(source) == Heap::PRE_HEAP) { |
---|
604 | _heap->push(source, capacity); |
---|
605 | } |
---|
606 | } |
---|
607 | |
---|
608 | /// \brief Processes the next node in the priority heap |
---|
609 | /// |
---|
610 | /// Processes the next node in the priority heap. |
---|
611 | /// |
---|
612 | /// \return The processed node. |
---|
613 | /// |
---|
614 | /// \warning The priority heap must not be empty! |
---|
615 | Node processNextNode() { |
---|
616 | Node node = _heap->top(); |
---|
617 | finalizeNodeData(node, _heap->prio()); |
---|
618 | _heap->pop(); |
---|
619 | |
---|
620 | for (InArcIt it(*_graph, node); it != INVALID; ++it) { |
---|
621 | Node source = _graph->source(it); |
---|
622 | switch (_heap->state(source)) { |
---|
623 | case Heap::PRE_HEAP: |
---|
624 | _heap->push(source, (*_capacity)[it]); |
---|
625 | break; |
---|
626 | case Heap::IN_HEAP: |
---|
627 | _heap->decrease(source, (*_heap)[source] + (*_capacity)[it]); |
---|
628 | break; |
---|
629 | case Heap::POST_HEAP: |
---|
630 | break; |
---|
631 | } |
---|
632 | } |
---|
633 | return node; |
---|
634 | } |
---|
635 | |
---|
636 | /// \brief Next node to be processed. |
---|
637 | /// |
---|
638 | /// Next node to be processed. |
---|
639 | /// |
---|
640 | /// \return The next node to be processed or INVALID if the |
---|
641 | /// priority heap is empty. |
---|
642 | Node nextNode() { |
---|
643 | return !_heap->empty() ? _heap->top() : INVALID; |
---|
644 | } |
---|
645 | |
---|
646 | /// \brief Returns \c false if there are nodes |
---|
647 | /// to be processed in the priority heap |
---|
648 | /// |
---|
649 | /// Returns \c false if there are nodes |
---|
650 | /// to be processed in the priority heap |
---|
651 | bool emptyQueue() { return _heap->empty(); } |
---|
652 | /// \brief Returns the number of the nodes to be processed |
---|
653 | /// in the priority heap |
---|
654 | /// |
---|
655 | /// Returns the number of the nodes to be processed in the priority heap |
---|
656 | int emptySize() { return _heap->size(); } |
---|
657 | |
---|
658 | /// \brief Executes the algorithm. |
---|
659 | /// |
---|
660 | /// Executes the algorithm. |
---|
661 | /// |
---|
662 | ///\pre init() must be called and at least one node should be added |
---|
663 | /// with addSource() before using this function. |
---|
664 | /// |
---|
665 | /// This method runs the Maximum Cardinality Search algorithm from the |
---|
666 | /// source node(s). |
---|
667 | void start() { |
---|
668 | while ( !_heap->empty() ) processNextNode(); |
---|
669 | } |
---|
670 | |
---|
671 | /// \brief Executes the algorithm until \c dest is reached. |
---|
672 | /// |
---|
673 | /// Executes the algorithm until \c dest is reached. |
---|
674 | /// |
---|
675 | /// \pre init() must be called and at least one node should be added |
---|
676 | /// with addSource() before using this function. |
---|
677 | /// |
---|
678 | /// This method runs the %MaxCardinalitySearch algorithm from the source |
---|
679 | /// nodes. |
---|
680 | void start(Node dest) { |
---|
681 | while ( !_heap->empty() && _heap->top()!=dest ) processNextNode(); |
---|
682 | if ( !_heap->empty() ) finalizeNodeData(_heap->top(), _heap->prio()); |
---|
683 | } |
---|
684 | |
---|
685 | /// \brief Executes the algorithm until a condition is met. |
---|
686 | /// |
---|
687 | /// Executes the algorithm until a condition is met. |
---|
688 | /// |
---|
689 | /// \pre init() must be called and at least one node should be added |
---|
690 | /// with addSource() before using this function. |
---|
691 | /// |
---|
692 | /// \param nm must be a bool (or convertible) node map. The algorithm |
---|
693 | /// will stop when it reaches a node \c v with <tt>nm[v]==true</tt>. |
---|
694 | template <typename NodeBoolMap> |
---|
695 | void start(const NodeBoolMap &nm) { |
---|
696 | while ( !_heap->empty() && !nm[_heap->top()] ) processNextNode(); |
---|
697 | if ( !_heap->empty() ) finalizeNodeData(_heap->top(),_heap->prio()); |
---|
698 | } |
---|
699 | |
---|
700 | /// \brief Runs the maximum cardinality search algorithm from node \c s. |
---|
701 | /// |
---|
702 | /// This method runs the %MaxCardinalitySearch algorithm from a root |
---|
703 | /// node \c s. |
---|
704 | /// |
---|
705 | ///\note d.run(s) is just a shortcut of the following code. |
---|
706 | ///\code |
---|
707 | /// d.init(); |
---|
708 | /// d.addSource(s); |
---|
709 | /// d.start(); |
---|
710 | ///\endcode |
---|
711 | void run(Node s) { |
---|
712 | init(); |
---|
713 | addSource(s); |
---|
714 | start(); |
---|
715 | } |
---|
716 | |
---|
717 | /// \brief Runs the maximum cardinality search algorithm for the |
---|
718 | /// whole digraph. |
---|
719 | /// |
---|
720 | /// This method runs the %MaxCardinalitySearch algorithm from all |
---|
721 | /// unprocessed node of the digraph. |
---|
722 | /// |
---|
723 | ///\note d.run(s) is just a shortcut of the following code. |
---|
724 | ///\code |
---|
725 | /// d.init(); |
---|
726 | /// for (NodeIt it(digraph); it != INVALID; ++it) { |
---|
727 | /// if (!d.reached(it)) { |
---|
728 | /// d.addSource(s); |
---|
729 | /// d.start(); |
---|
730 | /// } |
---|
731 | /// } |
---|
732 | ///\endcode |
---|
733 | void run() { |
---|
734 | init(); |
---|
735 | for (NodeIt it(*_graph); it != INVALID; ++it) { |
---|
736 | if (!reached(it)) { |
---|
737 | addSource(it); |
---|
738 | start(); |
---|
739 | } |
---|
740 | } |
---|
741 | } |
---|
742 | |
---|
743 | ///@} |
---|
744 | |
---|
745 | /// \name Query Functions |
---|
746 | /// The results of the maximum cardinality search algorithm can be |
---|
747 | /// obtained using these functions. |
---|
748 | /// \n |
---|
749 | /// Before the use of these functions, either run() or start() must be |
---|
750 | /// called. |
---|
751 | |
---|
752 | ///@{ |
---|
753 | |
---|
754 | /// \brief The cardinality of a node. |
---|
755 | /// |
---|
756 | /// Returns the cardinality of a node. |
---|
757 | /// \pre \ref run() must be called before using this function. |
---|
758 | /// \warning If node \c v in unreachable from the root the return value |
---|
759 | /// of this funcion is undefined. |
---|
760 | Value cardinality(Node node) const { return (*_cardinality)[node]; } |
---|
761 | |
---|
762 | /// \brief The current cardinality of a node. |
---|
763 | /// |
---|
764 | /// Returns the current cardinality of a node. |
---|
765 | /// \pre the given node should be reached but not processed |
---|
766 | Value currentCardinality(Node node) const { return (*_heap)[node]; } |
---|
767 | |
---|
768 | /// \brief Returns a reference to the NodeMap of cardinalities. |
---|
769 | /// |
---|
770 | /// Returns a reference to the NodeMap of cardinalities. \pre \ref run() |
---|
771 | /// must be called before using this function. |
---|
772 | const CardinalityMap &cardinalityMap() const { return *_cardinality;} |
---|
773 | |
---|
774 | /// \brief Checks if a node is reachable from the root. |
---|
775 | /// |
---|
776 | /// Returns \c true if \c v is reachable from the root. |
---|
777 | /// \warning The source nodes are initated as unreached. |
---|
778 | /// \pre \ref run() must be called before using this function. |
---|
779 | bool reached(Node v) { return (*_heap_cross_ref)[v] != Heap::PRE_HEAP; } |
---|
780 | |
---|
781 | /// \brief Checks if a node is processed. |
---|
782 | /// |
---|
783 | /// Returns \c true if \c v is processed, i.e. the shortest |
---|
784 | /// path to \c v has already found. |
---|
785 | /// \pre \ref run() must be called before using this function. |
---|
786 | bool processed(Node v) { return (*_heap_cross_ref)[v] == Heap::POST_HEAP; } |
---|
787 | |
---|
788 | ///@} |
---|
789 | }; |
---|
790 | |
---|
791 | } |
---|
792 | |
---|
793 | #endif |
---|