1 | /* -*- mode: C++; indent-tabs-mode: nil; -*- |
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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_SMART_GRAPH_H |
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20 | #define LEMON_SMART_GRAPH_H |
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21 | |
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22 | ///\ingroup graphs |
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23 | ///\file |
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24 | ///\brief SmartDigraph and SmartGraph classes. |
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25 | |
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26 | #include <vector> |
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27 | |
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28 | #include <lemon/core.h> |
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29 | #include <lemon/error.h> |
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30 | #include <lemon/bits/graph_extender.h> |
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31 | |
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32 | namespace lemon { |
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33 | |
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34 | class SmartDigraph; |
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35 | |
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36 | class SmartDigraphBase { |
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37 | protected: |
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38 | |
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39 | struct NodeT |
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40 | { |
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41 | int first_in, first_out; |
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42 | NodeT() {} |
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43 | }; |
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44 | struct ArcT |
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45 | { |
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46 | int target, source, next_in, next_out; |
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47 | ArcT() {} |
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48 | }; |
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49 | |
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50 | std::vector<NodeT> nodes; |
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51 | std::vector<ArcT> arcs; |
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52 | |
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53 | public: |
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54 | |
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55 | typedef SmartDigraphBase Digraph; |
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56 | |
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57 | class Node; |
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58 | class Arc; |
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59 | |
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60 | public: |
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61 | |
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62 | SmartDigraphBase() : nodes(), arcs() { } |
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63 | SmartDigraphBase(const SmartDigraphBase &_g) |
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64 | : nodes(_g.nodes), arcs(_g.arcs) { } |
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65 | |
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66 | typedef True NodeNumTag; |
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67 | typedef True ArcNumTag; |
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68 | |
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69 | int nodeNum() const { return nodes.size(); } |
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70 | int arcNum() const { return arcs.size(); } |
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71 | |
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72 | int maxNodeId() const { return nodes.size()-1; } |
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73 | int maxArcId() const { return arcs.size()-1; } |
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74 | |
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75 | Node addNode() { |
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76 | int n = nodes.size(); |
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77 | nodes.push_back(NodeT()); |
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78 | nodes[n].first_in = -1; |
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79 | nodes[n].first_out = -1; |
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80 | return Node(n); |
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81 | } |
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82 | |
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83 | Arc addArc(Node u, Node v) { |
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84 | int n = arcs.size(); |
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85 | arcs.push_back(ArcT()); |
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86 | arcs[n].source = u._id; |
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87 | arcs[n].target = v._id; |
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88 | arcs[n].next_out = nodes[u._id].first_out; |
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89 | arcs[n].next_in = nodes[v._id].first_in; |
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90 | nodes[u._id].first_out = nodes[v._id].first_in = n; |
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91 | |
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92 | return Arc(n); |
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93 | } |
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94 | |
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95 | void clear() { |
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96 | arcs.clear(); |
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97 | nodes.clear(); |
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98 | } |
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99 | |
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100 | Node source(Arc a) const { return Node(arcs[a._id].source); } |
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101 | Node target(Arc a) const { return Node(arcs[a._id].target); } |
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102 | |
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103 | static int id(Node v) { return v._id; } |
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104 | static int id(Arc a) { return a._id; } |
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105 | |
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106 | static Node nodeFromId(int id) { return Node(id);} |
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107 | static Arc arcFromId(int id) { return Arc(id);} |
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108 | |
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109 | bool valid(Node n) const { |
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110 | return n._id >= 0 && n._id < static_cast<int>(nodes.size()); |
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111 | } |
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112 | bool valid(Arc a) const { |
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113 | return a._id >= 0 && a._id < static_cast<int>(arcs.size()); |
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114 | } |
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115 | |
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116 | class Node { |
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117 | friend class SmartDigraphBase; |
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118 | friend class SmartDigraph; |
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119 | |
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120 | protected: |
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121 | int _id; |
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122 | explicit Node(int id) : _id(id) {} |
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123 | public: |
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124 | Node() {} |
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125 | Node (Invalid) : _id(-1) {} |
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126 | bool operator==(const Node i) const {return _id == i._id;} |
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127 | bool operator!=(const Node i) const {return _id != i._id;} |
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128 | bool operator<(const Node i) const {return _id < i._id;} |
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129 | }; |
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130 | |
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131 | |
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132 | class Arc { |
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133 | friend class SmartDigraphBase; |
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134 | friend class SmartDigraph; |
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135 | |
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136 | protected: |
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137 | int _id; |
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138 | explicit Arc(int id) : _id(id) {} |
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139 | public: |
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140 | Arc() { } |
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141 | Arc (Invalid) : _id(-1) {} |
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142 | bool operator==(const Arc i) const {return _id == i._id;} |
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143 | bool operator!=(const Arc i) const {return _id != i._id;} |
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144 | bool operator<(const Arc i) const {return _id < i._id;} |
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145 | }; |
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146 | |
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147 | void first(Node& node) const { |
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148 | node._id = nodes.size() - 1; |
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149 | } |
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150 | |
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151 | static void next(Node& node) { |
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152 | --node._id; |
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153 | } |
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154 | |
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155 | void first(Arc& arc) const { |
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156 | arc._id = arcs.size() - 1; |
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157 | } |
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158 | |
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159 | static void next(Arc& arc) { |
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160 | --arc._id; |
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161 | } |
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162 | |
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163 | void firstOut(Arc& arc, const Node& node) const { |
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164 | arc._id = nodes[node._id].first_out; |
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165 | } |
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166 | |
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167 | void nextOut(Arc& arc) const { |
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168 | arc._id = arcs[arc._id].next_out; |
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169 | } |
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170 | |
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171 | void firstIn(Arc& arc, const Node& node) const { |
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172 | arc._id = nodes[node._id].first_in; |
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173 | } |
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174 | |
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175 | void nextIn(Arc& arc) const { |
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176 | arc._id = arcs[arc._id].next_in; |
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177 | } |
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178 | |
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179 | }; |
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180 | |
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181 | typedef DigraphExtender<SmartDigraphBase> ExtendedSmartDigraphBase; |
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182 | |
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183 | ///\ingroup graphs |
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184 | /// |
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185 | ///\brief A smart directed graph class. |
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186 | /// |
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187 | ///\ref SmartDigraph is a simple and fast digraph implementation. |
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188 | ///It is also quite memory efficient but at the price |
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189 | ///that it does not support node and arc deletion |
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190 | ///(except for the Snapshot feature). |
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191 | /// |
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192 | ///This type fully conforms to the \ref concepts::Digraph "Digraph concept" |
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193 | ///and it also provides some additional functionalities. |
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194 | ///Most of its member functions and nested classes are documented |
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195 | ///only in the concept class. |
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196 | /// |
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197 | ///This class provides constant time counting for nodes and arcs. |
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198 | /// |
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199 | ///\sa concepts::Digraph |
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200 | ///\sa SmartGraph |
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201 | class SmartDigraph : public ExtendedSmartDigraphBase { |
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202 | typedef ExtendedSmartDigraphBase Parent; |
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203 | |
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204 | private: |
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205 | /// Digraphs are \e not copy constructible. Use DigraphCopy instead. |
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206 | SmartDigraph(const SmartDigraph &) : ExtendedSmartDigraphBase() {}; |
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207 | /// \brief Assignment of a digraph to another one is \e not allowed. |
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208 | /// Use DigraphCopy instead. |
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209 | void operator=(const SmartDigraph &) {} |
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210 | |
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211 | public: |
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212 | |
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213 | /// Constructor |
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214 | |
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215 | /// Constructor. |
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216 | /// |
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217 | SmartDigraph() {}; |
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218 | |
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219 | ///Add a new node to the digraph. |
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220 | |
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221 | ///This function adds a new node to the digraph. |
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222 | ///\return The new node. |
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223 | Node addNode() { return Parent::addNode(); } |
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224 | |
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225 | ///Add a new arc to the digraph. |
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226 | |
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227 | ///This function adds a new arc to the digraph with source node \c s |
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228 | ///and target node \c t. |
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229 | ///\return The new arc. |
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230 | Arc addArc(Node s, Node t) { |
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231 | return Parent::addArc(s, t); |
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232 | } |
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233 | |
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234 | /// \brief Node validity check |
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235 | /// |
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236 | /// This function gives back \c true if the given node is valid, |
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237 | /// i.e. it is a real node of the digraph. |
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238 | /// |
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239 | /// \warning A removed node (using Snapshot) could become valid again |
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240 | /// if new nodes are added to the digraph. |
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241 | bool valid(Node n) const { return Parent::valid(n); } |
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242 | |
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243 | /// \brief Arc validity check |
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244 | /// |
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245 | /// This function gives back \c true if the given arc is valid, |
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246 | /// i.e. it is a real arc of the digraph. |
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247 | /// |
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248 | /// \warning A removed arc (using Snapshot) could become valid again |
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249 | /// if new arcs are added to the graph. |
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250 | bool valid(Arc a) const { return Parent::valid(a); } |
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251 | |
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252 | ///Split a node. |
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253 | |
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254 | ///This function splits the given node. First, a new node is added |
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255 | ///to the digraph, then the source of each outgoing arc of node \c n |
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256 | ///is moved to this new node. |
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257 | ///If the second parameter \c connect is \c true (this is the default |
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258 | ///value), then a new arc from node \c n to the newly created node |
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259 | ///is also added. |
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260 | ///\return The newly created node. |
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261 | /// |
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262 | ///\note All iterators remain valid. |
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263 | /// |
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264 | ///\warning This functionality cannot be used together with the Snapshot |
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265 | ///feature. |
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266 | Node split(Node n, bool connect = true) |
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267 | { |
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268 | Node b = addNode(); |
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269 | nodes[b._id].first_out=nodes[n._id].first_out; |
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270 | nodes[n._id].first_out=-1; |
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271 | for(int i=nodes[b._id].first_out; i!=-1; i=arcs[i].next_out) { |
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272 | arcs[i].source=b._id; |
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273 | } |
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274 | if(connect) addArc(n,b); |
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275 | return b; |
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276 | } |
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277 | |
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278 | ///Clear the digraph. |
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279 | |
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280 | ///This function erases all nodes and arcs from the digraph. |
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281 | /// |
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282 | void clear() { |
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283 | Parent::clear(); |
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284 | } |
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285 | |
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286 | /// Reserve memory for nodes. |
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287 | |
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288 | /// Using this function, it is possible to avoid superfluous memory |
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289 | /// allocation: if you know that the digraph you want to build will |
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290 | /// be large (e.g. it will contain millions of nodes and/or arcs), |
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291 | /// then it is worth reserving space for this amount before starting |
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292 | /// to build the digraph. |
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293 | /// \sa reserveArc() |
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294 | void reserveNode(int n) { nodes.reserve(n); }; |
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295 | |
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296 | /// Reserve memory for arcs. |
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297 | |
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298 | /// Using this function, it is possible to avoid superfluous memory |
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299 | /// allocation: if you know that the digraph you want to build will |
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300 | /// be large (e.g. it will contain millions of nodes and/or arcs), |
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301 | /// then it is worth reserving space for this amount before starting |
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302 | /// to build the digraph. |
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303 | /// \sa reserveNode() |
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304 | void reserveArc(int m) { arcs.reserve(m); }; |
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305 | |
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306 | public: |
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307 | |
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308 | class Snapshot; |
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309 | |
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310 | protected: |
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311 | |
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312 | void restoreSnapshot(const Snapshot &s) |
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313 | { |
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314 | while(s.arc_num<arcs.size()) { |
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315 | Arc arc = arcFromId(arcs.size()-1); |
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316 | Parent::notifier(Arc()).erase(arc); |
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317 | nodes[arcs.back().source].first_out=arcs.back().next_out; |
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318 | nodes[arcs.back().target].first_in=arcs.back().next_in; |
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319 | arcs.pop_back(); |
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320 | } |
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321 | while(s.node_num<nodes.size()) { |
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322 | Node node = nodeFromId(nodes.size()-1); |
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323 | Parent::notifier(Node()).erase(node); |
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324 | nodes.pop_back(); |
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325 | } |
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326 | } |
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327 | |
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328 | public: |
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329 | |
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330 | ///Class to make a snapshot of the digraph and to restore it later. |
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331 | |
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332 | ///Class to make a snapshot of the digraph and to restore it later. |
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333 | /// |
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334 | ///The newly added nodes and arcs can be removed using the |
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335 | ///restore() function. This is the only way for deleting nodes and/or |
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336 | ///arcs from a SmartDigraph structure. |
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337 | /// |
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338 | ///\note After a state is restored, you cannot restore a later state, |
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339 | ///i.e. you cannot add the removed nodes and arcs again using |
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340 | ///another Snapshot instance. |
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341 | /// |
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342 | ///\warning Node splitting cannot be restored. |
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343 | ///\warning The validity of the snapshot is not stored due to |
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344 | ///performance reasons. If you do not use the snapshot correctly, |
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345 | ///it can cause broken program, invalid or not restored state of |
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346 | ///the digraph or no change. |
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347 | class Snapshot |
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348 | { |
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349 | SmartDigraph *_graph; |
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350 | protected: |
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351 | friend class SmartDigraph; |
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352 | unsigned int node_num; |
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353 | unsigned int arc_num; |
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354 | public: |
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355 | ///Default constructor. |
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356 | |
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357 | ///Default constructor. |
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358 | ///You have to call save() to actually make a snapshot. |
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359 | Snapshot() : _graph(0) {} |
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360 | ///Constructor that immediately makes a snapshot |
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361 | |
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362 | ///This constructor immediately makes a snapshot of the given digraph. |
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363 | /// |
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364 | Snapshot(SmartDigraph &gr) : _graph(&gr) { |
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365 | node_num=_graph->nodes.size(); |
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366 | arc_num=_graph->arcs.size(); |
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367 | } |
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368 | |
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369 | ///Make a snapshot. |
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370 | |
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371 | ///This function makes a snapshot of the given digraph. |
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372 | ///It can be called more than once. In case of a repeated |
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373 | ///call, the previous snapshot gets lost. |
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374 | void save(SmartDigraph &gr) { |
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375 | _graph=&gr; |
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376 | node_num=_graph->nodes.size(); |
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377 | arc_num=_graph->arcs.size(); |
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378 | } |
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379 | |
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380 | ///Undo the changes until a snapshot. |
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381 | |
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382 | ///This function undos the changes until the last snapshot |
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383 | ///created by save() or Snapshot(SmartDigraph&). |
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384 | void restore() |
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385 | { |
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386 | _graph->restoreSnapshot(*this); |
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387 | } |
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388 | }; |
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389 | }; |
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390 | |
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391 | |
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392 | class SmartGraphBase { |
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393 | |
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394 | protected: |
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395 | |
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396 | struct NodeT { |
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397 | int first_out; |
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398 | }; |
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399 | |
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400 | struct ArcT { |
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401 | int target; |
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402 | int next_out; |
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403 | }; |
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404 | |
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405 | std::vector<NodeT> nodes; |
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406 | std::vector<ArcT> arcs; |
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407 | |
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408 | public: |
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409 | |
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410 | typedef SmartGraphBase Graph; |
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411 | |
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412 | class Node; |
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413 | class Arc; |
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414 | class Edge; |
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415 | |
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416 | class Node { |
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417 | friend class SmartGraphBase; |
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418 | protected: |
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419 | |
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420 | int _id; |
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421 | explicit Node(int id) { _id = id;} |
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422 | |
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423 | public: |
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424 | Node() {} |
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425 | Node (Invalid) { _id = -1; } |
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426 | bool operator==(const Node& node) const {return _id == node._id;} |
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427 | bool operator!=(const Node& node) const {return _id != node._id;} |
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428 | bool operator<(const Node& node) const {return _id < node._id;} |
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429 | }; |
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430 | |
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431 | class Edge { |
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432 | friend class SmartGraphBase; |
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433 | protected: |
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434 | |
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435 | int _id; |
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436 | explicit Edge(int id) { _id = id;} |
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437 | |
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438 | public: |
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439 | Edge() {} |
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440 | Edge (Invalid) { _id = -1; } |
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441 | bool operator==(const Edge& arc) const {return _id == arc._id;} |
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442 | bool operator!=(const Edge& arc) const {return _id != arc._id;} |
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443 | bool operator<(const Edge& arc) const {return _id < arc._id;} |
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444 | }; |
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445 | |
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446 | class Arc { |
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447 | friend class SmartGraphBase; |
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448 | protected: |
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449 | |
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450 | int _id; |
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451 | explicit Arc(int id) { _id = id;} |
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452 | |
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453 | public: |
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454 | operator Edge() const { |
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455 | return _id != -1 ? edgeFromId(_id / 2) : INVALID; |
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456 | } |
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457 | |
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458 | Arc() {} |
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459 | Arc (Invalid) { _id = -1; } |
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460 | bool operator==(const Arc& arc) const {return _id == arc._id;} |
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461 | bool operator!=(const Arc& arc) const {return _id != arc._id;} |
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462 | bool operator<(const Arc& arc) const {return _id < arc._id;} |
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463 | }; |
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464 | |
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465 | |
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466 | |
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467 | SmartGraphBase() |
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468 | : nodes(), arcs() {} |
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469 | |
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470 | typedef True NodeNumTag; |
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471 | typedef True EdgeNumTag; |
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472 | typedef True ArcNumTag; |
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473 | |
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474 | int nodeNum() const { return nodes.size(); } |
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475 | int edgeNum() const { return arcs.size() / 2; } |
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476 | int arcNum() const { return arcs.size(); } |
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477 | |
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478 | int maxNodeId() const { return nodes.size()-1; } |
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479 | int maxEdgeId() const { return arcs.size() / 2 - 1; } |
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480 | int maxArcId() const { return arcs.size()-1; } |
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481 | |
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482 | Node source(Arc e) const { return Node(arcs[e._id ^ 1].target); } |
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483 | Node target(Arc e) const { return Node(arcs[e._id].target); } |
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484 | |
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485 | Node u(Edge e) const { return Node(arcs[2 * e._id].target); } |
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486 | Node v(Edge e) const { return Node(arcs[2 * e._id + 1].target); } |
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487 | |
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488 | static bool direction(Arc e) { |
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489 | return (e._id & 1) == 1; |
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490 | } |
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491 | |
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492 | static Arc direct(Edge e, bool d) { |
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493 | return Arc(e._id * 2 + (d ? 1 : 0)); |
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494 | } |
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495 | |
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496 | void first(Node& node) const { |
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497 | node._id = nodes.size() - 1; |
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498 | } |
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499 | |
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500 | static void next(Node& node) { |
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501 | --node._id; |
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502 | } |
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503 | |
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504 | void first(Arc& arc) const { |
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505 | arc._id = arcs.size() - 1; |
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506 | } |
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507 | |
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508 | static void next(Arc& arc) { |
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509 | --arc._id; |
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510 | } |
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511 | |
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512 | void first(Edge& arc) const { |
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513 | arc._id = arcs.size() / 2 - 1; |
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514 | } |
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515 | |
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516 | static void next(Edge& arc) { |
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517 | --arc._id; |
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518 | } |
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519 | |
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520 | void firstOut(Arc &arc, const Node& v) const { |
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521 | arc._id = nodes[v._id].first_out; |
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522 | } |
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523 | void nextOut(Arc &arc) const { |
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524 | arc._id = arcs[arc._id].next_out; |
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525 | } |
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526 | |
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527 | void firstIn(Arc &arc, const Node& v) const { |
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528 | arc._id = ((nodes[v._id].first_out) ^ 1); |
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529 | if (arc._id == -2) arc._id = -1; |
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530 | } |
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531 | void nextIn(Arc &arc) const { |
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532 | arc._id = ((arcs[arc._id ^ 1].next_out) ^ 1); |
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533 | if (arc._id == -2) arc._id = -1; |
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534 | } |
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535 | |
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536 | void firstInc(Edge &arc, bool& d, const Node& v) const { |
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537 | int de = nodes[v._id].first_out; |
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538 | if (de != -1) { |
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539 | arc._id = de / 2; |
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540 | d = ((de & 1) == 1); |
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541 | } else { |
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542 | arc._id = -1; |
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543 | d = true; |
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544 | } |
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545 | } |
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546 | void nextInc(Edge &arc, bool& d) const { |
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547 | int de = (arcs[(arc._id * 2) | (d ? 1 : 0)].next_out); |
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548 | if (de != -1) { |
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549 | arc._id = de / 2; |
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550 | d = ((de & 1) == 1); |
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551 | } else { |
---|
552 | arc._id = -1; |
---|
553 | d = true; |
---|
554 | } |
---|
555 | } |
---|
556 | |
---|
557 | static int id(Node v) { return v._id; } |
---|
558 | static int id(Arc e) { return e._id; } |
---|
559 | static int id(Edge e) { return e._id; } |
---|
560 | |
---|
561 | static Node nodeFromId(int id) { return Node(id);} |
---|
562 | static Arc arcFromId(int id) { return Arc(id);} |
---|
563 | static Edge edgeFromId(int id) { return Edge(id);} |
---|
564 | |
---|
565 | bool valid(Node n) const { |
---|
566 | return n._id >= 0 && n._id < static_cast<int>(nodes.size()); |
---|
567 | } |
---|
568 | bool valid(Arc a) const { |
---|
569 | return a._id >= 0 && a._id < static_cast<int>(arcs.size()); |
---|
570 | } |
---|
571 | bool valid(Edge e) const { |
---|
572 | return e._id >= 0 && 2 * e._id < static_cast<int>(arcs.size()); |
---|
573 | } |
---|
574 | |
---|
575 | Node addNode() { |
---|
576 | int n = nodes.size(); |
---|
577 | nodes.push_back(NodeT()); |
---|
578 | nodes[n].first_out = -1; |
---|
579 | |
---|
580 | return Node(n); |
---|
581 | } |
---|
582 | |
---|
583 | Edge addEdge(Node u, Node v) { |
---|
584 | int n = arcs.size(); |
---|
585 | arcs.push_back(ArcT()); |
---|
586 | arcs.push_back(ArcT()); |
---|
587 | |
---|
588 | arcs[n].target = u._id; |
---|
589 | arcs[n | 1].target = v._id; |
---|
590 | |
---|
591 | arcs[n].next_out = nodes[v._id].first_out; |
---|
592 | nodes[v._id].first_out = n; |
---|
593 | |
---|
594 | arcs[n | 1].next_out = nodes[u._id].first_out; |
---|
595 | nodes[u._id].first_out = (n | 1); |
---|
596 | |
---|
597 | return Edge(n / 2); |
---|
598 | } |
---|
599 | |
---|
600 | void clear() { |
---|
601 | arcs.clear(); |
---|
602 | nodes.clear(); |
---|
603 | } |
---|
604 | |
---|
605 | }; |
---|
606 | |
---|
607 | typedef GraphExtender<SmartGraphBase> ExtendedSmartGraphBase; |
---|
608 | |
---|
609 | /// \ingroup graphs |
---|
610 | /// |
---|
611 | /// \brief A smart undirected graph class. |
---|
612 | /// |
---|
613 | /// \ref SmartGraph is a simple and fast graph implementation. |
---|
614 | /// It is also quite memory efficient but at the price |
---|
615 | /// that it does not support node and edge deletion |
---|
616 | /// (except for the Snapshot feature). |
---|
617 | /// |
---|
618 | /// This type fully conforms to the \ref concepts::Graph "Graph concept" |
---|
619 | /// and it also provides some additional functionalities. |
---|
620 | /// Most of its member functions and nested classes are documented |
---|
621 | /// only in the concept class. |
---|
622 | /// |
---|
623 | /// This class provides constant time counting for nodes, edges and arcs. |
---|
624 | /// |
---|
625 | /// \sa concepts::Graph |
---|
626 | /// \sa SmartDigraph |
---|
627 | class SmartGraph : public ExtendedSmartGraphBase { |
---|
628 | typedef ExtendedSmartGraphBase Parent; |
---|
629 | |
---|
630 | private: |
---|
631 | /// Graphs are \e not copy constructible. Use GraphCopy instead. |
---|
632 | SmartGraph(const SmartGraph &) : ExtendedSmartGraphBase() {}; |
---|
633 | /// \brief Assignment of a graph to another one is \e not allowed. |
---|
634 | /// Use GraphCopy instead. |
---|
635 | void operator=(const SmartGraph &) {} |
---|
636 | |
---|
637 | public: |
---|
638 | |
---|
639 | /// Constructor |
---|
640 | |
---|
641 | /// Constructor. |
---|
642 | /// |
---|
643 | SmartGraph() {} |
---|
644 | |
---|
645 | /// \brief Add a new node to the graph. |
---|
646 | /// |
---|
647 | /// This function adds a new node to the graph. |
---|
648 | /// \return The new node. |
---|
649 | Node addNode() { return Parent::addNode(); } |
---|
650 | |
---|
651 | /// \brief Add a new edge to the graph. |
---|
652 | /// |
---|
653 | /// This function adds a new edge to the graph between nodes |
---|
654 | /// \c u and \c v with inherent orientation from node \c u to |
---|
655 | /// node \c v. |
---|
656 | /// \return The new edge. |
---|
657 | Edge addEdge(Node u, Node v) { |
---|
658 | return Parent::addEdge(u, v); |
---|
659 | } |
---|
660 | |
---|
661 | /// \brief Node validity check |
---|
662 | /// |
---|
663 | /// This function gives back \c true if the given node is valid, |
---|
664 | /// i.e. it is a real node of the graph. |
---|
665 | /// |
---|
666 | /// \warning A removed node (using Snapshot) could become valid again |
---|
667 | /// if new nodes are added to the graph. |
---|
668 | bool valid(Node n) const { return Parent::valid(n); } |
---|
669 | |
---|
670 | /// \brief Edge validity check |
---|
671 | /// |
---|
672 | /// This function gives back \c true if the given edge is valid, |
---|
673 | /// i.e. it is a real edge of the graph. |
---|
674 | /// |
---|
675 | /// \warning A removed edge (using Snapshot) could become valid again |
---|
676 | /// if new edges are added to the graph. |
---|
677 | bool valid(Edge e) const { return Parent::valid(e); } |
---|
678 | |
---|
679 | /// \brief Arc validity check |
---|
680 | /// |
---|
681 | /// This function gives back \c true if the given arc is valid, |
---|
682 | /// i.e. it is a real arc of the graph. |
---|
683 | /// |
---|
684 | /// \warning A removed arc (using Snapshot) could become valid again |
---|
685 | /// if new edges are added to the graph. |
---|
686 | bool valid(Arc a) const { return Parent::valid(a); } |
---|
687 | |
---|
688 | ///Clear the graph. |
---|
689 | |
---|
690 | ///This function erases all nodes and arcs from the graph. |
---|
691 | /// |
---|
692 | void clear() { |
---|
693 | Parent::clear(); |
---|
694 | } |
---|
695 | |
---|
696 | /// Reserve memory for nodes. |
---|
697 | |
---|
698 | /// Using this function, it is possible to avoid superfluous memory |
---|
699 | /// allocation: if you know that the graph you want to build will |
---|
700 | /// be large (e.g. it will contain millions of nodes and/or edges), |
---|
701 | /// then it is worth reserving space for this amount before starting |
---|
702 | /// to build the graph. |
---|
703 | /// \sa reserveEdge() |
---|
704 | void reserveNode(int n) { nodes.reserve(n); }; |
---|
705 | |
---|
706 | /// Reserve memory for edges. |
---|
707 | |
---|
708 | /// Using this function, it is possible to avoid superfluous memory |
---|
709 | /// allocation: if you know that the graph you want to build will |
---|
710 | /// be large (e.g. it will contain millions of nodes and/or edges), |
---|
711 | /// then it is worth reserving space for this amount before starting |
---|
712 | /// to build the graph. |
---|
713 | /// \sa reserveNode() |
---|
714 | void reserveEdge(int m) { arcs.reserve(2 * m); }; |
---|
715 | |
---|
716 | public: |
---|
717 | |
---|
718 | class Snapshot; |
---|
719 | |
---|
720 | protected: |
---|
721 | |
---|
722 | void saveSnapshot(Snapshot &s) |
---|
723 | { |
---|
724 | s._graph = this; |
---|
725 | s.node_num = nodes.size(); |
---|
726 | s.arc_num = arcs.size(); |
---|
727 | } |
---|
728 | |
---|
729 | void restoreSnapshot(const Snapshot &s) |
---|
730 | { |
---|
731 | while(s.arc_num<arcs.size()) { |
---|
732 | int n=arcs.size()-1; |
---|
733 | Edge arc=edgeFromId(n/2); |
---|
734 | Parent::notifier(Edge()).erase(arc); |
---|
735 | std::vector<Arc> dir; |
---|
736 | dir.push_back(arcFromId(n)); |
---|
737 | dir.push_back(arcFromId(n-1)); |
---|
738 | Parent::notifier(Arc()).erase(dir); |
---|
739 | nodes[arcs[n-1].target].first_out=arcs[n].next_out; |
---|
740 | nodes[arcs[n].target].first_out=arcs[n-1].next_out; |
---|
741 | arcs.pop_back(); |
---|
742 | arcs.pop_back(); |
---|
743 | } |
---|
744 | while(s.node_num<nodes.size()) { |
---|
745 | int n=nodes.size()-1; |
---|
746 | Node node = nodeFromId(n); |
---|
747 | Parent::notifier(Node()).erase(node); |
---|
748 | nodes.pop_back(); |
---|
749 | } |
---|
750 | } |
---|
751 | |
---|
752 | public: |
---|
753 | |
---|
754 | ///Class to make a snapshot of the graph and to restore it later. |
---|
755 | |
---|
756 | ///Class to make a snapshot of the graph and to restore it later. |
---|
757 | /// |
---|
758 | ///The newly added nodes and edges can be removed using the |
---|
759 | ///restore() function. This is the only way for deleting nodes and/or |
---|
760 | ///edges from a SmartGraph structure. |
---|
761 | /// |
---|
762 | ///\note After a state is restored, you cannot restore a later state, |
---|
763 | ///i.e. you cannot add the removed nodes and edges again using |
---|
764 | ///another Snapshot instance. |
---|
765 | /// |
---|
766 | ///\warning The validity of the snapshot is not stored due to |
---|
767 | ///performance reasons. If you do not use the snapshot correctly, |
---|
768 | ///it can cause broken program, invalid or not restored state of |
---|
769 | ///the graph or no change. |
---|
770 | class Snapshot |
---|
771 | { |
---|
772 | SmartGraph *_graph; |
---|
773 | protected: |
---|
774 | friend class SmartGraph; |
---|
775 | unsigned int node_num; |
---|
776 | unsigned int arc_num; |
---|
777 | public: |
---|
778 | ///Default constructor. |
---|
779 | |
---|
780 | ///Default constructor. |
---|
781 | ///You have to call save() to actually make a snapshot. |
---|
782 | Snapshot() : _graph(0) {} |
---|
783 | ///Constructor that immediately makes a snapshot |
---|
784 | |
---|
785 | /// This constructor immediately makes a snapshot of the given graph. |
---|
786 | /// |
---|
787 | Snapshot(SmartGraph &gr) { |
---|
788 | gr.saveSnapshot(*this); |
---|
789 | } |
---|
790 | |
---|
791 | ///Make a snapshot. |
---|
792 | |
---|
793 | ///This function makes a snapshot of the given graph. |
---|
794 | ///It can be called more than once. In case of a repeated |
---|
795 | ///call, the previous snapshot gets lost. |
---|
796 | void save(SmartGraph &gr) |
---|
797 | { |
---|
798 | gr.saveSnapshot(*this); |
---|
799 | } |
---|
800 | |
---|
801 | ///Undo the changes until the last snapshot. |
---|
802 | |
---|
803 | ///This function undos the changes until the last snapshot |
---|
804 | ///created by save() or Snapshot(SmartGraph&). |
---|
805 | void restore() |
---|
806 | { |
---|
807 | _graph->restoreSnapshot(*this); |
---|
808 | } |
---|
809 | }; |
---|
810 | }; |
---|
811 | |
---|
812 | class SmartBpGraphBase { |
---|
813 | |
---|
814 | protected: |
---|
815 | |
---|
816 | struct NodeT { |
---|
817 | int first_out; |
---|
818 | int partition_next; |
---|
819 | int partition_index; |
---|
820 | bool red; |
---|
821 | }; |
---|
822 | |
---|
823 | struct ArcT { |
---|
824 | int target; |
---|
825 | int next_out; |
---|
826 | }; |
---|
827 | |
---|
828 | std::vector<NodeT> nodes; |
---|
829 | std::vector<ArcT> arcs; |
---|
830 | |
---|
831 | int first_red, first_blue; |
---|
832 | int max_red, max_blue; |
---|
833 | |
---|
834 | public: |
---|
835 | |
---|
836 | typedef SmartBpGraphBase Graph; |
---|
837 | |
---|
838 | class Node; |
---|
839 | class Arc; |
---|
840 | class Edge; |
---|
841 | |
---|
842 | class Node { |
---|
843 | friend class SmartBpGraphBase; |
---|
844 | protected: |
---|
845 | |
---|
846 | int _id; |
---|
847 | explicit Node(int id) { _id = id;} |
---|
848 | |
---|
849 | public: |
---|
850 | Node() {} |
---|
851 | Node (Invalid) { _id = -1; } |
---|
852 | bool operator==(const Node& node) const {return _id == node._id;} |
---|
853 | bool operator!=(const Node& node) const {return _id != node._id;} |
---|
854 | bool operator<(const Node& node) const {return _id < node._id;} |
---|
855 | }; |
---|
856 | |
---|
857 | class Edge { |
---|
858 | friend class SmartBpGraphBase; |
---|
859 | protected: |
---|
860 | |
---|
861 | int _id; |
---|
862 | explicit Edge(int id) { _id = id;} |
---|
863 | |
---|
864 | public: |
---|
865 | Edge() {} |
---|
866 | Edge (Invalid) { _id = -1; } |
---|
867 | bool operator==(const Edge& arc) const {return _id == arc._id;} |
---|
868 | bool operator!=(const Edge& arc) const {return _id != arc._id;} |
---|
869 | bool operator<(const Edge& arc) const {return _id < arc._id;} |
---|
870 | }; |
---|
871 | |
---|
872 | class Arc { |
---|
873 | friend class SmartBpGraphBase; |
---|
874 | protected: |
---|
875 | |
---|
876 | int _id; |
---|
877 | explicit Arc(int id) { _id = id;} |
---|
878 | |
---|
879 | public: |
---|
880 | operator Edge() const { |
---|
881 | return _id != -1 ? edgeFromId(_id / 2) : INVALID; |
---|
882 | } |
---|
883 | |
---|
884 | Arc() {} |
---|
885 | Arc (Invalid) { _id = -1; } |
---|
886 | bool operator==(const Arc& arc) const {return _id == arc._id;} |
---|
887 | bool operator!=(const Arc& arc) const {return _id != arc._id;} |
---|
888 | bool operator<(const Arc& arc) const {return _id < arc._id;} |
---|
889 | }; |
---|
890 | |
---|
891 | |
---|
892 | |
---|
893 | SmartBpGraphBase() |
---|
894 | : nodes(), arcs(), first_red(-1), first_blue(-1), |
---|
895 | max_red(-1), max_blue(-1) {} |
---|
896 | |
---|
897 | typedef True NodeNumTag; |
---|
898 | typedef True EdgeNumTag; |
---|
899 | typedef True ArcNumTag; |
---|
900 | |
---|
901 | int nodeNum() const { return nodes.size(); } |
---|
902 | int redNum() const { return max_red + 1; } |
---|
903 | int blueNum() const { return max_blue + 1; } |
---|
904 | int edgeNum() const { return arcs.size() / 2; } |
---|
905 | int arcNum() const { return arcs.size(); } |
---|
906 | |
---|
907 | int maxNodeId() const { return nodes.size()-1; } |
---|
908 | int maxRedId() const { return max_red; } |
---|
909 | int maxBlueId() const { return max_blue; } |
---|
910 | int maxEdgeId() const { return arcs.size() / 2 - 1; } |
---|
911 | int maxArcId() const { return arcs.size()-1; } |
---|
912 | |
---|
913 | bool red(Node n) const { return nodes[n._id].red; } |
---|
914 | bool blue(Node n) const { return !nodes[n._id].red; } |
---|
915 | |
---|
916 | Node source(Arc a) const { return Node(arcs[a._id ^ 1].target); } |
---|
917 | Node target(Arc a) const { return Node(arcs[a._id].target); } |
---|
918 | |
---|
919 | Node redNode(Edge e) const { return Node(arcs[2 * e._id].target); } |
---|
920 | Node blueNode(Edge e) const { return Node(arcs[2 * e._id + 1].target); } |
---|
921 | |
---|
922 | static bool direction(Arc a) { |
---|
923 | return (a._id & 1) == 1; |
---|
924 | } |
---|
925 | |
---|
926 | static Arc direct(Edge e, bool d) { |
---|
927 | return Arc(e._id * 2 + (d ? 1 : 0)); |
---|
928 | } |
---|
929 | |
---|
930 | void first(Node& node) const { |
---|
931 | node._id = nodes.size() - 1; |
---|
932 | } |
---|
933 | |
---|
934 | static void next(Node& node) { |
---|
935 | --node._id; |
---|
936 | } |
---|
937 | |
---|
938 | void firstRed(Node& node) const { |
---|
939 | node._id = first_red; |
---|
940 | } |
---|
941 | |
---|
942 | void nextRed(Node& node) const { |
---|
943 | node._id = nodes[node._id].partition_next; |
---|
944 | } |
---|
945 | |
---|
946 | void firstBlue(Node& node) const { |
---|
947 | node._id = first_blue; |
---|
948 | } |
---|
949 | |
---|
950 | void nextBlue(Node& node) const { |
---|
951 | node._id = nodes[node._id].partition_next; |
---|
952 | } |
---|
953 | |
---|
954 | void first(Arc& arc) const { |
---|
955 | arc._id = arcs.size() - 1; |
---|
956 | } |
---|
957 | |
---|
958 | static void next(Arc& arc) { |
---|
959 | --arc._id; |
---|
960 | } |
---|
961 | |
---|
962 | void first(Edge& arc) const { |
---|
963 | arc._id = arcs.size() / 2 - 1; |
---|
964 | } |
---|
965 | |
---|
966 | static void next(Edge& arc) { |
---|
967 | --arc._id; |
---|
968 | } |
---|
969 | |
---|
970 | void firstOut(Arc &arc, const Node& v) const { |
---|
971 | arc._id = nodes[v._id].first_out; |
---|
972 | } |
---|
973 | void nextOut(Arc &arc) const { |
---|
974 | arc._id = arcs[arc._id].next_out; |
---|
975 | } |
---|
976 | |
---|
977 | void firstIn(Arc &arc, const Node& v) const { |
---|
978 | arc._id = ((nodes[v._id].first_out) ^ 1); |
---|
979 | if (arc._id == -2) arc._id = -1; |
---|
980 | } |
---|
981 | void nextIn(Arc &arc) const { |
---|
982 | arc._id = ((arcs[arc._id ^ 1].next_out) ^ 1); |
---|
983 | if (arc._id == -2) arc._id = -1; |
---|
984 | } |
---|
985 | |
---|
986 | void firstInc(Edge &arc, bool& d, const Node& v) const { |
---|
987 | int de = nodes[v._id].first_out; |
---|
988 | if (de != -1) { |
---|
989 | arc._id = de / 2; |
---|
990 | d = ((de & 1) == 1); |
---|
991 | } else { |
---|
992 | arc._id = -1; |
---|
993 | d = true; |
---|
994 | } |
---|
995 | } |
---|
996 | void nextInc(Edge &arc, bool& d) const { |
---|
997 | int de = (arcs[(arc._id * 2) | (d ? 1 : 0)].next_out); |
---|
998 | if (de != -1) { |
---|
999 | arc._id = de / 2; |
---|
1000 | d = ((de & 1) == 1); |
---|
1001 | } else { |
---|
1002 | arc._id = -1; |
---|
1003 | d = true; |
---|
1004 | } |
---|
1005 | } |
---|
1006 | |
---|
1007 | static int id(Node v) { return v._id; } |
---|
1008 | int redId(Node v) const { |
---|
1009 | LEMON_DEBUG(nodes[v._id].red, "Node has to be red"); |
---|
1010 | return nodes[v._id].partition_index; |
---|
1011 | } |
---|
1012 | int blueId(Node v) const { |
---|
1013 | LEMON_DEBUG(!nodes[v._id].red, "Node has to be blue"); |
---|
1014 | return nodes[v._id].partition_index; |
---|
1015 | } |
---|
1016 | static int id(Arc e) { return e._id; } |
---|
1017 | static int id(Edge e) { return e._id; } |
---|
1018 | |
---|
1019 | static Node nodeFromId(int id) { return Node(id);} |
---|
1020 | static Arc arcFromId(int id) { return Arc(id);} |
---|
1021 | static Edge edgeFromId(int id) { return Edge(id);} |
---|
1022 | |
---|
1023 | bool valid(Node n) const { |
---|
1024 | return n._id >= 0 && n._id < static_cast<int>(nodes.size()); |
---|
1025 | } |
---|
1026 | bool valid(Arc a) const { |
---|
1027 | return a._id >= 0 && a._id < static_cast<int>(arcs.size()); |
---|
1028 | } |
---|
1029 | bool valid(Edge e) const { |
---|
1030 | return e._id >= 0 && 2 * e._id < static_cast<int>(arcs.size()); |
---|
1031 | } |
---|
1032 | |
---|
1033 | Node addRedNode() { |
---|
1034 | int n = nodes.size(); |
---|
1035 | nodes.push_back(NodeT()); |
---|
1036 | nodes[n].first_out = -1; |
---|
1037 | nodes[n].red = true; |
---|
1038 | nodes[n].partition_index = ++max_red; |
---|
1039 | nodes[n].partition_next = first_red; |
---|
1040 | first_red = n; |
---|
1041 | |
---|
1042 | return Node(n); |
---|
1043 | } |
---|
1044 | |
---|
1045 | Node addBlueNode() { |
---|
1046 | int n = nodes.size(); |
---|
1047 | nodes.push_back(NodeT()); |
---|
1048 | nodes[n].first_out = -1; |
---|
1049 | nodes[n].red = false; |
---|
1050 | nodes[n].partition_index = ++max_blue; |
---|
1051 | nodes[n].partition_next = first_blue; |
---|
1052 | first_blue = n; |
---|
1053 | |
---|
1054 | return Node(n); |
---|
1055 | } |
---|
1056 | |
---|
1057 | Edge addEdge(Node u, Node v) { |
---|
1058 | int n = arcs.size(); |
---|
1059 | arcs.push_back(ArcT()); |
---|
1060 | arcs.push_back(ArcT()); |
---|
1061 | |
---|
1062 | arcs[n].target = u._id; |
---|
1063 | arcs[n | 1].target = v._id; |
---|
1064 | |
---|
1065 | arcs[n].next_out = nodes[v._id].first_out; |
---|
1066 | nodes[v._id].first_out = n; |
---|
1067 | |
---|
1068 | arcs[n | 1].next_out = nodes[u._id].first_out; |
---|
1069 | nodes[u._id].first_out = (n | 1); |
---|
1070 | |
---|
1071 | return Edge(n / 2); |
---|
1072 | } |
---|
1073 | |
---|
1074 | void clear() { |
---|
1075 | arcs.clear(); |
---|
1076 | nodes.clear(); |
---|
1077 | first_red = -1; |
---|
1078 | first_blue = -1; |
---|
1079 | max_blue = -1; |
---|
1080 | max_red = -1; |
---|
1081 | } |
---|
1082 | |
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1083 | }; |
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1084 | |
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1085 | typedef BpGraphExtender<SmartBpGraphBase> ExtendedSmartBpGraphBase; |
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1086 | |
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1087 | /// \ingroup graphs |
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1088 | /// |
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1089 | /// \brief A smart undirected bipartite graph class. |
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1090 | /// |
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1091 | /// \ref SmartBpGraph is a simple and fast bipartite graph implementation. |
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1092 | /// It is also quite memory efficient but at the price |
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1093 | /// that it does not support node and edge deletion |
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1094 | /// (except for the Snapshot feature). |
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1095 | /// |
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1096 | /// This type fully conforms to the \ref concepts::BpGraph "BpGraph concept" |
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1097 | /// and it also provides some additional functionalities. |
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1098 | /// Most of its member functions and nested classes are documented |
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1099 | /// only in the concept class. |
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1100 | /// |
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1101 | /// This class provides constant time counting for nodes, edges and arcs. |
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1102 | /// |
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1103 | /// \sa concepts::BpGraph |
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1104 | /// \sa SmartGraph |
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1105 | class SmartBpGraph : public ExtendedSmartBpGraphBase { |
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1106 | typedef ExtendedSmartBpGraphBase Parent; |
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1107 | |
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1108 | private: |
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1109 | /// Graphs are \e not copy constructible. Use GraphCopy instead. |
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1110 | SmartBpGraph(const SmartBpGraph &) : ExtendedSmartBpGraphBase() {}; |
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1111 | /// \brief Assignment of a graph to another one is \e not allowed. |
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1112 | /// Use GraphCopy instead. |
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1113 | void operator=(const SmartBpGraph &) {} |
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1114 | |
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1115 | public: |
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1116 | |
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1117 | /// Constructor |
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1118 | |
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1119 | /// Constructor. |
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1120 | /// |
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1121 | SmartBpGraph() {} |
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1122 | |
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1123 | /// \brief Add a new red node to the graph. |
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1124 | /// |
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1125 | /// This function adds a red new node to the graph. |
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1126 | /// \return The new node. |
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1127 | Node addRedNode() { return Parent::addRedNode(); } |
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1128 | |
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1129 | /// \brief Add a new blue node to the graph. |
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1130 | /// |
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1131 | /// This function adds a blue new node to the graph. |
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1132 | /// \return The new node. |
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1133 | Node addBlueNode() { return Parent::addBlueNode(); } |
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1134 | |
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1135 | /// \brief Add a new edge to the graph. |
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1136 | /// |
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1137 | /// This function adds a new edge to the graph between nodes |
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1138 | /// \c u and \c v with inherent orientation from node \c u to |
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1139 | /// node \c v. |
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1140 | /// \return The new edge. |
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1141 | Edge addEdge(Node red, Node blue) { |
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1142 | LEMON_DEBUG(Parent::red(red) && Parent::blue(blue), |
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1143 | "Edge has to be formed by a red and a blue nodes"); |
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1144 | return Parent::addEdge(red, blue); |
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1145 | } |
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1146 | |
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1147 | /// \brief Node validity check |
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1148 | /// |
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1149 | /// This function gives back \c true if the given node is valid, |
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1150 | /// i.e. it is a real node of the graph. |
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1151 | /// |
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1152 | /// \warning A removed node (using Snapshot) could become valid again |
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1153 | /// if new nodes are added to the graph. |
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1154 | bool valid(Node n) const { return Parent::valid(n); } |
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1155 | |
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1156 | /// \brief Edge validity check |
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1157 | /// |
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1158 | /// This function gives back \c true if the given edge is valid, |
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1159 | /// i.e. it is a real edge of the graph. |
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1160 | /// |
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1161 | /// \warning A removed edge (using Snapshot) could become valid again |
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1162 | /// if new edges are added to the graph. |
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1163 | bool valid(Edge e) const { return Parent::valid(e); } |
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1164 | |
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1165 | /// \brief Arc validity check |
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1166 | /// |
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1167 | /// This function gives back \c true if the given arc is valid, |
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1168 | /// i.e. it is a real arc of the graph. |
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1169 | /// |
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1170 | /// \warning A removed arc (using Snapshot) could become valid again |
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1171 | /// if new edges are added to the graph. |
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1172 | bool valid(Arc a) const { return Parent::valid(a); } |
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1173 | |
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1174 | ///Clear the graph. |
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1175 | |
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1176 | ///This function erases all nodes and arcs from the graph. |
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1177 | /// |
---|
1178 | void clear() { |
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1179 | Parent::clear(); |
---|
1180 | } |
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1181 | |
---|
1182 | /// Reserve memory for nodes. |
---|
1183 | |
---|
1184 | /// Using this function, it is possible to avoid superfluous memory |
---|
1185 | /// allocation: if you know that the graph you want to build will |
---|
1186 | /// be large (e.g. it will contain millions of nodes and/or edges), |
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1187 | /// then it is worth reserving space for this amount before starting |
---|
1188 | /// to build the graph. |
---|
1189 | /// \sa reserveEdge() |
---|
1190 | void reserveNode(int n) { nodes.reserve(n); }; |
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1191 | |
---|
1192 | /// Reserve memory for edges. |
---|
1193 | |
---|
1194 | /// Using this function, it is possible to avoid superfluous memory |
---|
1195 | /// allocation: if you know that the graph you want to build will |
---|
1196 | /// be large (e.g. it will contain millions of nodes and/or edges), |
---|
1197 | /// then it is worth reserving space for this amount before starting |
---|
1198 | /// to build the graph. |
---|
1199 | /// \sa reserveNode() |
---|
1200 | void reserveEdge(int m) { arcs.reserve(2 * m); }; |
---|
1201 | |
---|
1202 | public: |
---|
1203 | |
---|
1204 | class Snapshot; |
---|
1205 | |
---|
1206 | protected: |
---|
1207 | |
---|
1208 | void saveSnapshot(Snapshot &s) |
---|
1209 | { |
---|
1210 | s._graph = this; |
---|
1211 | s.node_num = nodes.size(); |
---|
1212 | s.arc_num = arcs.size(); |
---|
1213 | } |
---|
1214 | |
---|
1215 | void restoreSnapshot(const Snapshot &s) |
---|
1216 | { |
---|
1217 | while(s.arc_num<arcs.size()) { |
---|
1218 | int n=arcs.size()-1; |
---|
1219 | Edge arc=edgeFromId(n/2); |
---|
1220 | Parent::notifier(Edge()).erase(arc); |
---|
1221 | std::vector<Arc> dir; |
---|
1222 | dir.push_back(arcFromId(n)); |
---|
1223 | dir.push_back(arcFromId(n-1)); |
---|
1224 | Parent::notifier(Arc()).erase(dir); |
---|
1225 | nodes[arcs[n-1].target].first_out=arcs[n].next_out; |
---|
1226 | nodes[arcs[n].target].first_out=arcs[n-1].next_out; |
---|
1227 | arcs.pop_back(); |
---|
1228 | arcs.pop_back(); |
---|
1229 | } |
---|
1230 | while(s.node_num<nodes.size()) { |
---|
1231 | int n=nodes.size()-1; |
---|
1232 | Node node = nodeFromId(n); |
---|
1233 | if (Parent::red(node)) { |
---|
1234 | first_red = nodes[n].partition_next; |
---|
1235 | if (first_red != -1) { |
---|
1236 | max_red = nodes[first_red].partition_index; |
---|
1237 | } else { |
---|
1238 | max_red = -1; |
---|
1239 | } |
---|
1240 | Parent::notifier(RedNode()).erase(node); |
---|
1241 | } else { |
---|
1242 | first_blue = nodes[n].partition_next; |
---|
1243 | if (first_blue != -1) { |
---|
1244 | max_blue = nodes[first_blue].partition_index; |
---|
1245 | } else { |
---|
1246 | max_blue = -1; |
---|
1247 | } |
---|
1248 | Parent::notifier(BlueNode()).erase(node); |
---|
1249 | } |
---|
1250 | Parent::notifier(Node()).erase(node); |
---|
1251 | nodes.pop_back(); |
---|
1252 | } |
---|
1253 | } |
---|
1254 | |
---|
1255 | public: |
---|
1256 | |
---|
1257 | ///Class to make a snapshot of the graph and to restore it later. |
---|
1258 | |
---|
1259 | ///Class to make a snapshot of the graph and to restore it later. |
---|
1260 | /// |
---|
1261 | ///The newly added nodes and edges can be removed using the |
---|
1262 | ///restore() function. This is the only way for deleting nodes and/or |
---|
1263 | ///edges from a SmartBpGraph structure. |
---|
1264 | /// |
---|
1265 | ///\note After a state is restored, you cannot restore a later state, |
---|
1266 | ///i.e. you cannot add the removed nodes and edges again using |
---|
1267 | ///another Snapshot instance. |
---|
1268 | /// |
---|
1269 | ///\warning The validity of the snapshot is not stored due to |
---|
1270 | ///performance reasons. If you do not use the snapshot correctly, |
---|
1271 | ///it can cause broken program, invalid or not restored state of |
---|
1272 | ///the graph or no change. |
---|
1273 | class Snapshot |
---|
1274 | { |
---|
1275 | SmartBpGraph *_graph; |
---|
1276 | protected: |
---|
1277 | friend class SmartBpGraph; |
---|
1278 | unsigned int node_num; |
---|
1279 | unsigned int arc_num; |
---|
1280 | public: |
---|
1281 | ///Default constructor. |
---|
1282 | |
---|
1283 | ///Default constructor. |
---|
1284 | ///You have to call save() to actually make a snapshot. |
---|
1285 | Snapshot() : _graph(0) {} |
---|
1286 | ///Constructor that immediately makes a snapshot |
---|
1287 | |
---|
1288 | /// This constructor immediately makes a snapshot of the given graph. |
---|
1289 | /// |
---|
1290 | Snapshot(SmartBpGraph &gr) { |
---|
1291 | gr.saveSnapshot(*this); |
---|
1292 | } |
---|
1293 | |
---|
1294 | ///Make a snapshot. |
---|
1295 | |
---|
1296 | ///This function makes a snapshot of the given graph. |
---|
1297 | ///It can be called more than once. In case of a repeated |
---|
1298 | ///call, the previous snapshot gets lost. |
---|
1299 | void save(SmartBpGraph &gr) |
---|
1300 | { |
---|
1301 | gr.saveSnapshot(*this); |
---|
1302 | } |
---|
1303 | |
---|
1304 | ///Undo the changes until the last snapshot. |
---|
1305 | |
---|
1306 | ///This function undos the changes until the last snapshot |
---|
1307 | ///created by save() or Snapshot(SmartBpGraph&). |
---|
1308 | void restore() |
---|
1309 | { |
---|
1310 | _graph->restoreSnapshot(*this); |
---|
1311 | } |
---|
1312 | }; |
---|
1313 | }; |
---|
1314 | |
---|
1315 | } //namespace lemon |
---|
1316 | |
---|
1317 | |
---|
1318 | #endif //LEMON_SMART_GRAPH_H |
---|