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_LIST_GRAPH_H |
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20 | #define LEMON_LIST_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 ListDigraph and ListGraph classes. |
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25 | |
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26 | #include <lemon/core.h> |
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27 | #include <lemon/error.h> |
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28 | #include <lemon/bits/graph_extender.h> |
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29 | |
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30 | #include <vector> |
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31 | #include <list> |
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32 | |
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33 | namespace lemon { |
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34 | |
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35 | class ListDigraph; |
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36 | |
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37 | class ListDigraphBase { |
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38 | |
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39 | protected: |
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40 | struct NodeT { |
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41 | int first_in, first_out; |
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42 | int prev, next; |
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43 | }; |
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44 | |
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45 | struct ArcT { |
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46 | int target, source; |
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47 | int prev_in, prev_out; |
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48 | int next_in, next_out; |
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49 | }; |
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50 | |
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51 | std::vector<NodeT> nodes; |
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52 | |
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53 | int first_node; |
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54 | |
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55 | int first_free_node; |
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56 | |
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57 | std::vector<ArcT> arcs; |
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58 | |
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59 | int first_free_arc; |
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60 | |
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61 | public: |
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62 | |
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63 | typedef ListDigraphBase Digraph; |
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64 | |
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65 | class Node { |
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66 | friend class ListDigraphBase; |
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67 | friend class ListDigraph; |
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68 | protected: |
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69 | |
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70 | int id; |
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71 | explicit Node(int pid) { id = pid;} |
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72 | |
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73 | public: |
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74 | Node() {} |
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75 | Node (Invalid) { id = -1; } |
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76 | bool operator==(const Node& node) const {return id == node.id;} |
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77 | bool operator!=(const Node& node) const {return id != node.id;} |
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78 | bool operator<(const Node& node) const {return id < node.id;} |
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79 | }; |
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80 | |
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81 | class Arc { |
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82 | friend class ListDigraphBase; |
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83 | friend class ListDigraph; |
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84 | protected: |
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85 | |
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86 | int id; |
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87 | explicit Arc(int pid) { id = pid;} |
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88 | |
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89 | public: |
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90 | Arc() {} |
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91 | Arc (Invalid) { id = -1; } |
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92 | bool operator==(const Arc& arc) const {return id == arc.id;} |
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93 | bool operator!=(const Arc& arc) const {return id != arc.id;} |
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94 | bool operator<(const Arc& arc) const {return id < arc.id;} |
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95 | }; |
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96 | |
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97 | |
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98 | |
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99 | ListDigraphBase() |
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100 | : nodes(), first_node(-1), |
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101 | first_free_node(-1), arcs(), first_free_arc(-1) {} |
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102 | |
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103 | |
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104 | int maxNodeId() const { return nodes.size()-1; } |
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105 | int maxArcId() const { return arcs.size()-1; } |
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106 | |
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107 | Node source(Arc e) const { return Node(arcs[e.id].source); } |
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108 | Node target(Arc e) const { return Node(arcs[e.id].target); } |
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109 | |
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110 | |
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111 | void first(Node& node) const { |
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112 | node.id = first_node; |
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113 | } |
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114 | |
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115 | void next(Node& node) const { |
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116 | node.id = nodes[node.id].next; |
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117 | } |
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118 | |
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119 | |
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120 | void first(Arc& arc) const { |
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121 | int n; |
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122 | for(n = first_node; |
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123 | n != -1 && nodes[n].first_out == -1; |
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124 | n = nodes[n].next) {} |
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125 | arc.id = (n == -1) ? -1 : nodes[n].first_out; |
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126 | } |
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127 | |
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128 | void next(Arc& arc) const { |
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129 | if (arcs[arc.id].next_out != -1) { |
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130 | arc.id = arcs[arc.id].next_out; |
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131 | } else { |
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132 | int n; |
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133 | for(n = nodes[arcs[arc.id].source].next; |
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134 | n != -1 && nodes[n].first_out == -1; |
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135 | n = nodes[n].next) {} |
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136 | arc.id = (n == -1) ? -1 : nodes[n].first_out; |
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137 | } |
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138 | } |
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139 | |
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140 | void firstOut(Arc &e, const Node& v) const { |
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141 | e.id = nodes[v.id].first_out; |
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142 | } |
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143 | void nextOut(Arc &e) const { |
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144 | e.id=arcs[e.id].next_out; |
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145 | } |
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146 | |
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147 | void firstIn(Arc &e, const Node& v) const { |
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148 | e.id = nodes[v.id].first_in; |
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149 | } |
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150 | void nextIn(Arc &e) const { |
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151 | e.id=arcs[e.id].next_in; |
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152 | } |
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153 | |
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154 | |
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155 | static int id(Node v) { return v.id; } |
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156 | static int id(Arc e) { return e.id; } |
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157 | |
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158 | static Node nodeFromId(int id) { return Node(id);} |
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159 | static Arc arcFromId(int id) { return Arc(id);} |
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160 | |
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161 | bool valid(Node n) const { |
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162 | return n.id >= 0 && n.id < static_cast<int>(nodes.size()) && |
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163 | nodes[n.id].prev != -2; |
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164 | } |
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165 | |
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166 | bool valid(Arc a) const { |
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167 | return a.id >= 0 && a.id < static_cast<int>(arcs.size()) && |
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168 | arcs[a.id].prev_in != -2; |
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169 | } |
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170 | |
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171 | Node addNode() { |
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172 | int n; |
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173 | |
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174 | if(first_free_node==-1) { |
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175 | n = nodes.size(); |
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176 | nodes.push_back(NodeT()); |
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177 | } else { |
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178 | n = first_free_node; |
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179 | first_free_node = nodes[n].next; |
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180 | } |
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181 | |
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182 | nodes[n].next = first_node; |
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183 | if(first_node != -1) nodes[first_node].prev = n; |
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184 | first_node = n; |
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185 | nodes[n].prev = -1; |
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186 | |
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187 | nodes[n].first_in = nodes[n].first_out = -1; |
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188 | |
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189 | return Node(n); |
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190 | } |
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191 | |
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192 | Arc addArc(Node u, Node v) { |
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193 | int n; |
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194 | |
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195 | if (first_free_arc == -1) { |
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196 | n = arcs.size(); |
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197 | arcs.push_back(ArcT()); |
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198 | } else { |
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199 | n = first_free_arc; |
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200 | first_free_arc = arcs[n].next_in; |
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201 | } |
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202 | |
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203 | arcs[n].source = u.id; |
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204 | arcs[n].target = v.id; |
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205 | |
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206 | arcs[n].next_out = nodes[u.id].first_out; |
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207 | if(nodes[u.id].first_out != -1) { |
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208 | arcs[nodes[u.id].first_out].prev_out = n; |
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209 | } |
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210 | |
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211 | arcs[n].next_in = nodes[v.id].first_in; |
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212 | if(nodes[v.id].first_in != -1) { |
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213 | arcs[nodes[v.id].first_in].prev_in = n; |
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214 | } |
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215 | |
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216 | arcs[n].prev_in = arcs[n].prev_out = -1; |
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217 | |
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218 | nodes[u.id].first_out = nodes[v.id].first_in = n; |
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219 | |
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220 | return Arc(n); |
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221 | } |
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222 | |
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223 | void erase(const Node& node) { |
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224 | int n = node.id; |
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225 | |
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226 | if(nodes[n].next != -1) { |
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227 | nodes[nodes[n].next].prev = nodes[n].prev; |
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228 | } |
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229 | |
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230 | if(nodes[n].prev != -1) { |
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231 | nodes[nodes[n].prev].next = nodes[n].next; |
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232 | } else { |
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233 | first_node = nodes[n].next; |
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234 | } |
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235 | |
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236 | nodes[n].next = first_free_node; |
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237 | first_free_node = n; |
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238 | nodes[n].prev = -2; |
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239 | |
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240 | } |
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241 | |
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242 | void erase(const Arc& arc) { |
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243 | int n = arc.id; |
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244 | |
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245 | if(arcs[n].next_in!=-1) { |
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246 | arcs[arcs[n].next_in].prev_in = arcs[n].prev_in; |
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247 | } |
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248 | |
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249 | if(arcs[n].prev_in!=-1) { |
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250 | arcs[arcs[n].prev_in].next_in = arcs[n].next_in; |
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251 | } else { |
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252 | nodes[arcs[n].target].first_in = arcs[n].next_in; |
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253 | } |
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254 | |
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255 | |
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256 | if(arcs[n].next_out!=-1) { |
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257 | arcs[arcs[n].next_out].prev_out = arcs[n].prev_out; |
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258 | } |
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259 | |
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260 | if(arcs[n].prev_out!=-1) { |
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261 | arcs[arcs[n].prev_out].next_out = arcs[n].next_out; |
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262 | } else { |
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263 | nodes[arcs[n].source].first_out = arcs[n].next_out; |
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264 | } |
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265 | |
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266 | arcs[n].next_in = first_free_arc; |
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267 | first_free_arc = n; |
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268 | arcs[n].prev_in = -2; |
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269 | } |
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270 | |
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271 | void clear() { |
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272 | arcs.clear(); |
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273 | nodes.clear(); |
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274 | first_node = first_free_node = first_free_arc = -1; |
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275 | } |
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276 | |
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277 | protected: |
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278 | void changeTarget(Arc e, Node n) |
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279 | { |
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280 | if(arcs[e.id].next_in != -1) |
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281 | arcs[arcs[e.id].next_in].prev_in = arcs[e.id].prev_in; |
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282 | if(arcs[e.id].prev_in != -1) |
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283 | arcs[arcs[e.id].prev_in].next_in = arcs[e.id].next_in; |
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284 | else nodes[arcs[e.id].target].first_in = arcs[e.id].next_in; |
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285 | if (nodes[n.id].first_in != -1) { |
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286 | arcs[nodes[n.id].first_in].prev_in = e.id; |
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287 | } |
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288 | arcs[e.id].target = n.id; |
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289 | arcs[e.id].prev_in = -1; |
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290 | arcs[e.id].next_in = nodes[n.id].first_in; |
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291 | nodes[n.id].first_in = e.id; |
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292 | } |
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293 | void changeSource(Arc e, Node n) |
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294 | { |
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295 | if(arcs[e.id].next_out != -1) |
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296 | arcs[arcs[e.id].next_out].prev_out = arcs[e.id].prev_out; |
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297 | if(arcs[e.id].prev_out != -1) |
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298 | arcs[arcs[e.id].prev_out].next_out = arcs[e.id].next_out; |
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299 | else nodes[arcs[e.id].source].first_out = arcs[e.id].next_out; |
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300 | if (nodes[n.id].first_out != -1) { |
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301 | arcs[nodes[n.id].first_out].prev_out = e.id; |
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302 | } |
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303 | arcs[e.id].source = n.id; |
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304 | arcs[e.id].prev_out = -1; |
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305 | arcs[e.id].next_out = nodes[n.id].first_out; |
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306 | nodes[n.id].first_out = e.id; |
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307 | } |
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308 | |
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309 | }; |
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310 | |
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311 | typedef DigraphExtender<ListDigraphBase> ExtendedListDigraphBase; |
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312 | |
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313 | /// \addtogroup graphs |
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314 | /// @{ |
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315 | |
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316 | ///A general directed graph structure. |
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317 | |
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318 | ///\ref ListDigraph is a versatile and fast directed graph |
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319 | ///implementation based on linked lists that are stored in |
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320 | ///\c std::vector structures. |
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321 | /// |
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322 | ///This type fully conforms to the \ref concepts::Digraph "Digraph concept" |
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323 | ///and it also provides several useful additional functionalities. |
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324 | ///Most of its member functions and nested classes are documented |
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325 | ///only in the concept class. |
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326 | /// |
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327 | ///This class provides only linear time counting for nodes and arcs. |
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328 | /// |
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329 | ///\sa concepts::Digraph |
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330 | ///\sa ListGraph |
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331 | class ListDigraph : public ExtendedListDigraphBase { |
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332 | typedef ExtendedListDigraphBase Parent; |
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333 | |
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334 | private: |
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335 | /// Digraphs are \e not copy constructible. Use DigraphCopy instead. |
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336 | ListDigraph(const ListDigraph &) :ExtendedListDigraphBase() {}; |
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337 | /// \brief Assignment of a digraph to another one is \e not allowed. |
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338 | /// Use DigraphCopy instead. |
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339 | void operator=(const ListDigraph &) {} |
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340 | public: |
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341 | |
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342 | /// Constructor |
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343 | |
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344 | /// Constructor. |
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345 | /// |
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346 | ListDigraph() {} |
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347 | |
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348 | ///Add a new node to the digraph. |
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349 | |
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350 | ///This function adds a new node to the digraph. |
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351 | ///\return The new node. |
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352 | Node addNode() { return Parent::addNode(); } |
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353 | |
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354 | ///Add a new arc to the digraph. |
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355 | |
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356 | ///This function adds a new arc to the digraph with source node \c s |
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357 | ///and target node \c t. |
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358 | ///\return The new arc. |
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359 | Arc addArc(Node s, Node t) { |
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360 | return Parent::addArc(s, t); |
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361 | } |
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362 | |
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363 | ///\brief Erase a node from the digraph. |
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364 | /// |
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365 | ///This function erases the given node along with its outgoing and |
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366 | ///incoming arcs from the digraph. |
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367 | /// |
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368 | ///\note All iterators referencing the removed node or the connected |
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369 | ///arcs are invalidated, of course. |
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370 | void erase(Node n) { Parent::erase(n); } |
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371 | |
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372 | ///\brief Erase an arc from the digraph. |
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373 | /// |
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374 | ///This function erases the given arc from the digraph. |
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375 | /// |
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376 | ///\note All iterators referencing the removed arc are invalidated, |
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377 | ///of course. |
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378 | void erase(Arc a) { Parent::erase(a); } |
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379 | |
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380 | /// Node validity check |
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381 | |
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382 | /// This function gives back \c true if the given node is valid, |
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383 | /// i.e. it is a real node of the digraph. |
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384 | /// |
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385 | /// \warning A removed node could become valid again if new nodes are |
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386 | /// added to the digraph. |
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387 | bool valid(Node n) const { return Parent::valid(n); } |
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388 | |
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389 | /// Arc validity check |
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390 | |
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391 | /// This function gives back \c true if the given arc is valid, |
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392 | /// i.e. it is a real arc of the digraph. |
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393 | /// |
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394 | /// \warning A removed arc could become valid again if new arcs are |
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395 | /// added to the digraph. |
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396 | bool valid(Arc a) const { return Parent::valid(a); } |
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397 | |
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398 | /// Change the target node of an arc |
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399 | |
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400 | /// This function changes the target node of the given arc \c a to \c n. |
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401 | /// |
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402 | ///\note \c ArcIt and \c OutArcIt iterators referencing the changed |
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403 | ///arc remain valid, but \c InArcIt iterators are invalidated. |
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404 | /// |
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405 | ///\warning This functionality cannot be used together with the Snapshot |
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406 | ///feature. |
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407 | void changeTarget(Arc a, Node n) { |
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408 | Parent::changeTarget(a,n); |
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409 | } |
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410 | /// Change the source node of an arc |
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411 | |
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412 | /// This function changes the source node of the given arc \c a to \c n. |
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413 | /// |
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414 | ///\note \c InArcIt iterators referencing the changed arc remain |
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415 | ///valid, but \c ArcIt and \c OutArcIt iterators are invalidated. |
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416 | /// |
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417 | ///\warning This functionality cannot be used together with the Snapshot |
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418 | ///feature. |
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419 | void changeSource(Arc a, Node n) { |
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420 | Parent::changeSource(a,n); |
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421 | } |
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422 | |
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423 | /// Reverse the direction of an arc. |
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424 | |
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425 | /// This function reverses the direction of the given arc. |
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426 | ///\note \c ArcIt, \c OutArcIt and \c InArcIt iterators referencing |
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427 | ///the changed arc are invalidated. |
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428 | /// |
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429 | ///\warning This functionality cannot be used together with the Snapshot |
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430 | ///feature. |
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431 | void reverseArc(Arc a) { |
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432 | Node t=target(a); |
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433 | changeTarget(a,source(a)); |
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434 | changeSource(a,t); |
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435 | } |
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436 | |
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437 | ///Contract two nodes. |
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438 | |
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439 | ///This function contracts the given two nodes. |
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440 | ///Node \c v is removed, but instead of deleting its |
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441 | ///incident arcs, they are joined to node \c u. |
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442 | ///If the last parameter \c r is \c true (this is the default value), |
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443 | ///then the newly created loops are removed. |
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444 | /// |
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445 | ///\note The moved arcs are joined to node \c u using changeSource() |
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446 | ///or changeTarget(), thus \c ArcIt and \c OutArcIt iterators are |
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447 | ///invalidated for the outgoing arcs of node \c v and \c InArcIt |
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448 | ///iterators are invalidated for the incomming arcs of \c v. |
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449 | ///Moreover all iterators referencing node \c v or the removed |
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450 | ///loops are also invalidated. Other iterators remain valid. |
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451 | /// |
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452 | ///\warning This functionality cannot be used together with the Snapshot |
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453 | ///feature. |
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454 | void contract(Node u, Node v, bool r = true) |
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455 | { |
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456 | for(OutArcIt e(*this,v);e!=INVALID;) { |
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457 | OutArcIt f=e; |
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458 | ++f; |
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459 | if(r && target(e)==u) erase(e); |
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460 | else changeSource(e,u); |
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461 | e=f; |
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462 | } |
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463 | for(InArcIt e(*this,v);e!=INVALID;) { |
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464 | InArcIt f=e; |
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465 | ++f; |
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466 | if(r && source(e)==u) erase(e); |
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467 | else changeTarget(e,u); |
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468 | e=f; |
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469 | } |
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470 | erase(v); |
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471 | } |
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472 | |
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473 | ///Split a node. |
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474 | |
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475 | ///This function splits the given node. First, a new node is added |
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476 | ///to the digraph, then the source of each outgoing arc of node \c n |
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477 | ///is moved to this new node. |
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478 | ///If the second parameter \c connect is \c true (this is the default |
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479 | ///value), then a new arc from node \c n to the newly created node |
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480 | ///is also added. |
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481 | ///\return The newly created node. |
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482 | /// |
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483 | ///\note All iterators remain valid. |
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484 | /// |
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485 | ///\warning This functionality cannot be used together with the |
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486 | ///Snapshot feature. |
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487 | Node split(Node n, bool connect = true) { |
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488 | Node b = addNode(); |
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489 | nodes[b.id].first_out=nodes[n.id].first_out; |
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490 | nodes[n.id].first_out=-1; |
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491 | for(int i=nodes[b.id].first_out; i!=-1; i=arcs[i].next_out) { |
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492 | arcs[i].source=b.id; |
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493 | } |
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494 | if (connect) addArc(n,b); |
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495 | return b; |
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496 | } |
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497 | |
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498 | ///Split an arc. |
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499 | |
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500 | ///This function splits the given arc. First, a new node \c v is |
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501 | ///added to the digraph, then the target node of the original arc |
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502 | ///is set to \c v. Finally, an arc from \c v to the original target |
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503 | ///is added. |
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504 | ///\return The newly created node. |
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505 | /// |
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506 | ///\note \c InArcIt iterators referencing the original arc are |
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507 | ///invalidated. Other iterators remain valid. |
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508 | /// |
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509 | ///\warning This functionality cannot be used together with the |
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510 | ///Snapshot feature. |
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511 | Node split(Arc a) { |
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512 | Node v = addNode(); |
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513 | addArc(v,target(a)); |
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514 | changeTarget(a,v); |
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515 | return v; |
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516 | } |
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517 | |
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518 | ///Clear the digraph. |
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519 | |
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520 | ///This function erases all nodes and arcs from the digraph. |
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521 | /// |
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522 | ///\note All iterators of the digraph are invalidated, of course. |
---|
523 | void clear() { |
---|
524 | Parent::clear(); |
---|
525 | } |
---|
526 | |
---|
527 | /// Reserve memory for nodes. |
---|
528 | |
---|
529 | /// Using this function, it is possible to avoid superfluous memory |
---|
530 | /// allocation: if you know that the digraph you want to build will |
---|
531 | /// be large (e.g. it will contain millions of nodes and/or arcs), |
---|
532 | /// then it is worth reserving space for this amount before starting |
---|
533 | /// to build the digraph. |
---|
534 | /// \sa reserveArc() |
---|
535 | void reserveNode(int n) { nodes.reserve(n); }; |
---|
536 | |
---|
537 | /// Reserve memory for arcs. |
---|
538 | |
---|
539 | /// Using this function, it is possible to avoid superfluous memory |
---|
540 | /// allocation: if you know that the digraph you want to build will |
---|
541 | /// be large (e.g. it will contain millions of nodes and/or arcs), |
---|
542 | /// then it is worth reserving space for this amount before starting |
---|
543 | /// to build the digraph. |
---|
544 | /// \sa reserveNode() |
---|
545 | void reserveArc(int m) { arcs.reserve(m); }; |
---|
546 | |
---|
547 | /// \brief Class to make a snapshot of the digraph and restore |
---|
548 | /// it later. |
---|
549 | /// |
---|
550 | /// Class to make a snapshot of the digraph and restore it later. |
---|
551 | /// |
---|
552 | /// The newly added nodes and arcs can be removed using the |
---|
553 | /// restore() function. |
---|
554 | /// |
---|
555 | /// \note After a state is restored, you cannot restore a later state, |
---|
556 | /// i.e. you cannot add the removed nodes and arcs again using |
---|
557 | /// another Snapshot instance. |
---|
558 | /// |
---|
559 | /// \warning Node and arc deletions and other modifications (e.g. |
---|
560 | /// reversing, contracting, splitting arcs or nodes) cannot be |
---|
561 | /// restored. These events invalidate the snapshot. |
---|
562 | /// However, the arcs and nodes that were added to the digraph after |
---|
563 | /// making the current snapshot can be removed without invalidating it. |
---|
564 | class Snapshot { |
---|
565 | protected: |
---|
566 | |
---|
567 | typedef Parent::NodeNotifier NodeNotifier; |
---|
568 | |
---|
569 | class NodeObserverProxy : public NodeNotifier::ObserverBase { |
---|
570 | public: |
---|
571 | |
---|
572 | NodeObserverProxy(Snapshot& _snapshot) |
---|
573 | : snapshot(_snapshot) {} |
---|
574 | |
---|
575 | using NodeNotifier::ObserverBase::attach; |
---|
576 | using NodeNotifier::ObserverBase::detach; |
---|
577 | using NodeNotifier::ObserverBase::attached; |
---|
578 | |
---|
579 | protected: |
---|
580 | |
---|
581 | virtual void add(const Node& node) { |
---|
582 | snapshot.addNode(node); |
---|
583 | } |
---|
584 | virtual void add(const std::vector<Node>& nodes) { |
---|
585 | for (int i = nodes.size() - 1; i >= 0; --i) { |
---|
586 | snapshot.addNode(nodes[i]); |
---|
587 | } |
---|
588 | } |
---|
589 | virtual void erase(const Node& node) { |
---|
590 | snapshot.eraseNode(node); |
---|
591 | } |
---|
592 | virtual void erase(const std::vector<Node>& nodes) { |
---|
593 | for (int i = 0; i < int(nodes.size()); ++i) { |
---|
594 | snapshot.eraseNode(nodes[i]); |
---|
595 | } |
---|
596 | } |
---|
597 | virtual void build() { |
---|
598 | Node node; |
---|
599 | std::vector<Node> nodes; |
---|
600 | for (notifier()->first(node); node != INVALID; |
---|
601 | notifier()->next(node)) { |
---|
602 | nodes.push_back(node); |
---|
603 | } |
---|
604 | for (int i = nodes.size() - 1; i >= 0; --i) { |
---|
605 | snapshot.addNode(nodes[i]); |
---|
606 | } |
---|
607 | } |
---|
608 | virtual void clear() { |
---|
609 | Node node; |
---|
610 | for (notifier()->first(node); node != INVALID; |
---|
611 | notifier()->next(node)) { |
---|
612 | snapshot.eraseNode(node); |
---|
613 | } |
---|
614 | } |
---|
615 | |
---|
616 | Snapshot& snapshot; |
---|
617 | }; |
---|
618 | |
---|
619 | class ArcObserverProxy : public ArcNotifier::ObserverBase { |
---|
620 | public: |
---|
621 | |
---|
622 | ArcObserverProxy(Snapshot& _snapshot) |
---|
623 | : snapshot(_snapshot) {} |
---|
624 | |
---|
625 | using ArcNotifier::ObserverBase::attach; |
---|
626 | using ArcNotifier::ObserverBase::detach; |
---|
627 | using ArcNotifier::ObserverBase::attached; |
---|
628 | |
---|
629 | protected: |
---|
630 | |
---|
631 | virtual void add(const Arc& arc) { |
---|
632 | snapshot.addArc(arc); |
---|
633 | } |
---|
634 | virtual void add(const std::vector<Arc>& arcs) { |
---|
635 | for (int i = arcs.size() - 1; i >= 0; --i) { |
---|
636 | snapshot.addArc(arcs[i]); |
---|
637 | } |
---|
638 | } |
---|
639 | virtual void erase(const Arc& arc) { |
---|
640 | snapshot.eraseArc(arc); |
---|
641 | } |
---|
642 | virtual void erase(const std::vector<Arc>& arcs) { |
---|
643 | for (int i = 0; i < int(arcs.size()); ++i) { |
---|
644 | snapshot.eraseArc(arcs[i]); |
---|
645 | } |
---|
646 | } |
---|
647 | virtual void build() { |
---|
648 | Arc arc; |
---|
649 | std::vector<Arc> arcs; |
---|
650 | for (notifier()->first(arc); arc != INVALID; |
---|
651 | notifier()->next(arc)) { |
---|
652 | arcs.push_back(arc); |
---|
653 | } |
---|
654 | for (int i = arcs.size() - 1; i >= 0; --i) { |
---|
655 | snapshot.addArc(arcs[i]); |
---|
656 | } |
---|
657 | } |
---|
658 | virtual void clear() { |
---|
659 | Arc arc; |
---|
660 | for (notifier()->first(arc); arc != INVALID; |
---|
661 | notifier()->next(arc)) { |
---|
662 | snapshot.eraseArc(arc); |
---|
663 | } |
---|
664 | } |
---|
665 | |
---|
666 | Snapshot& snapshot; |
---|
667 | }; |
---|
668 | |
---|
669 | ListDigraph *digraph; |
---|
670 | |
---|
671 | NodeObserverProxy node_observer_proxy; |
---|
672 | ArcObserverProxy arc_observer_proxy; |
---|
673 | |
---|
674 | std::list<Node> added_nodes; |
---|
675 | std::list<Arc> added_arcs; |
---|
676 | |
---|
677 | |
---|
678 | void addNode(const Node& node) { |
---|
679 | added_nodes.push_front(node); |
---|
680 | } |
---|
681 | void eraseNode(const Node& node) { |
---|
682 | std::list<Node>::iterator it = |
---|
683 | std::find(added_nodes.begin(), added_nodes.end(), node); |
---|
684 | if (it == added_nodes.end()) { |
---|
685 | clear(); |
---|
686 | arc_observer_proxy.detach(); |
---|
687 | throw NodeNotifier::ImmediateDetach(); |
---|
688 | } else { |
---|
689 | added_nodes.erase(it); |
---|
690 | } |
---|
691 | } |
---|
692 | |
---|
693 | void addArc(const Arc& arc) { |
---|
694 | added_arcs.push_front(arc); |
---|
695 | } |
---|
696 | void eraseArc(const Arc& arc) { |
---|
697 | std::list<Arc>::iterator it = |
---|
698 | std::find(added_arcs.begin(), added_arcs.end(), arc); |
---|
699 | if (it == added_arcs.end()) { |
---|
700 | clear(); |
---|
701 | node_observer_proxy.detach(); |
---|
702 | throw ArcNotifier::ImmediateDetach(); |
---|
703 | } else { |
---|
704 | added_arcs.erase(it); |
---|
705 | } |
---|
706 | } |
---|
707 | |
---|
708 | void attach(ListDigraph &_digraph) { |
---|
709 | digraph = &_digraph; |
---|
710 | node_observer_proxy.attach(digraph->notifier(Node())); |
---|
711 | arc_observer_proxy.attach(digraph->notifier(Arc())); |
---|
712 | } |
---|
713 | |
---|
714 | void detach() { |
---|
715 | node_observer_proxy.detach(); |
---|
716 | arc_observer_proxy.detach(); |
---|
717 | } |
---|
718 | |
---|
719 | bool attached() const { |
---|
720 | return node_observer_proxy.attached(); |
---|
721 | } |
---|
722 | |
---|
723 | void clear() { |
---|
724 | added_nodes.clear(); |
---|
725 | added_arcs.clear(); |
---|
726 | } |
---|
727 | |
---|
728 | public: |
---|
729 | |
---|
730 | /// \brief Default constructor. |
---|
731 | /// |
---|
732 | /// Default constructor. |
---|
733 | /// You have to call save() to actually make a snapshot. |
---|
734 | Snapshot() |
---|
735 | : digraph(0), node_observer_proxy(*this), |
---|
736 | arc_observer_proxy(*this) {} |
---|
737 | |
---|
738 | /// \brief Constructor that immediately makes a snapshot. |
---|
739 | /// |
---|
740 | /// This constructor immediately makes a snapshot of the given digraph. |
---|
741 | Snapshot(ListDigraph &gr) |
---|
742 | : node_observer_proxy(*this), |
---|
743 | arc_observer_proxy(*this) { |
---|
744 | attach(gr); |
---|
745 | } |
---|
746 | |
---|
747 | /// \brief Make a snapshot. |
---|
748 | /// |
---|
749 | /// This function makes a snapshot of the given digraph. |
---|
750 | /// It can be called more than once. In case of a repeated |
---|
751 | /// call, the previous snapshot gets lost. |
---|
752 | void save(ListDigraph &gr) { |
---|
753 | if (attached()) { |
---|
754 | detach(); |
---|
755 | clear(); |
---|
756 | } |
---|
757 | attach(gr); |
---|
758 | } |
---|
759 | |
---|
760 | /// \brief Undo the changes until the last snapshot. |
---|
761 | /// |
---|
762 | /// This function undos the changes until the last snapshot |
---|
763 | /// created by save() or Snapshot(ListDigraph&). |
---|
764 | /// |
---|
765 | /// \warning This method invalidates the snapshot, i.e. repeated |
---|
766 | /// restoring is not supported unless you call save() again. |
---|
767 | void restore() { |
---|
768 | detach(); |
---|
769 | for(std::list<Arc>::iterator it = added_arcs.begin(); |
---|
770 | it != added_arcs.end(); ++it) { |
---|
771 | digraph->erase(*it); |
---|
772 | } |
---|
773 | for(std::list<Node>::iterator it = added_nodes.begin(); |
---|
774 | it != added_nodes.end(); ++it) { |
---|
775 | digraph->erase(*it); |
---|
776 | } |
---|
777 | clear(); |
---|
778 | } |
---|
779 | |
---|
780 | /// \brief Returns \c true if the snapshot is valid. |
---|
781 | /// |
---|
782 | /// This function returns \c true if the snapshot is valid. |
---|
783 | bool valid() const { |
---|
784 | return attached(); |
---|
785 | } |
---|
786 | }; |
---|
787 | |
---|
788 | }; |
---|
789 | |
---|
790 | ///@} |
---|
791 | |
---|
792 | class ListGraphBase { |
---|
793 | |
---|
794 | protected: |
---|
795 | |
---|
796 | struct NodeT { |
---|
797 | int first_out; |
---|
798 | int prev, next; |
---|
799 | }; |
---|
800 | |
---|
801 | struct ArcT { |
---|
802 | int target; |
---|
803 | int prev_out, next_out; |
---|
804 | }; |
---|
805 | |
---|
806 | std::vector<NodeT> nodes; |
---|
807 | |
---|
808 | int first_node; |
---|
809 | |
---|
810 | int first_free_node; |
---|
811 | |
---|
812 | std::vector<ArcT> arcs; |
---|
813 | |
---|
814 | int first_free_arc; |
---|
815 | |
---|
816 | public: |
---|
817 | |
---|
818 | typedef ListGraphBase Graph; |
---|
819 | |
---|
820 | class Node { |
---|
821 | friend class ListGraphBase; |
---|
822 | protected: |
---|
823 | |
---|
824 | int id; |
---|
825 | explicit Node(int pid) { id = pid;} |
---|
826 | |
---|
827 | public: |
---|
828 | Node() {} |
---|
829 | Node (Invalid) { id = -1; } |
---|
830 | bool operator==(const Node& node) const {return id == node.id;} |
---|
831 | bool operator!=(const Node& node) const {return id != node.id;} |
---|
832 | bool operator<(const Node& node) const {return id < node.id;} |
---|
833 | }; |
---|
834 | |
---|
835 | class Edge { |
---|
836 | friend class ListGraphBase; |
---|
837 | protected: |
---|
838 | |
---|
839 | int id; |
---|
840 | explicit Edge(int pid) { id = pid;} |
---|
841 | |
---|
842 | public: |
---|
843 | Edge() {} |
---|
844 | Edge (Invalid) { id = -1; } |
---|
845 | bool operator==(const Edge& edge) const {return id == edge.id;} |
---|
846 | bool operator!=(const Edge& edge) const {return id != edge.id;} |
---|
847 | bool operator<(const Edge& edge) const {return id < edge.id;} |
---|
848 | }; |
---|
849 | |
---|
850 | class Arc { |
---|
851 | friend class ListGraphBase; |
---|
852 | protected: |
---|
853 | |
---|
854 | int id; |
---|
855 | explicit Arc(int pid) { id = pid;} |
---|
856 | |
---|
857 | public: |
---|
858 | operator Edge() const { |
---|
859 | return id != -1 ? edgeFromId(id / 2) : INVALID; |
---|
860 | } |
---|
861 | |
---|
862 | Arc() {} |
---|
863 | Arc (Invalid) { id = -1; } |
---|
864 | bool operator==(const Arc& arc) const {return id == arc.id;} |
---|
865 | bool operator!=(const Arc& arc) const {return id != arc.id;} |
---|
866 | bool operator<(const Arc& arc) const {return id < arc.id;} |
---|
867 | }; |
---|
868 | |
---|
869 | ListGraphBase() |
---|
870 | : nodes(), first_node(-1), |
---|
871 | first_free_node(-1), arcs(), first_free_arc(-1) {} |
---|
872 | |
---|
873 | |
---|
874 | int maxNodeId() const { return nodes.size()-1; } |
---|
875 | int maxEdgeId() const { return arcs.size() / 2 - 1; } |
---|
876 | int maxArcId() const { return arcs.size()-1; } |
---|
877 | |
---|
878 | Node source(Arc e) const { return Node(arcs[e.id ^ 1].target); } |
---|
879 | Node target(Arc e) const { return Node(arcs[e.id].target); } |
---|
880 | |
---|
881 | Node u(Edge e) const { return Node(arcs[2 * e.id].target); } |
---|
882 | Node v(Edge e) const { return Node(arcs[2 * e.id + 1].target); } |
---|
883 | |
---|
884 | static bool direction(Arc e) { |
---|
885 | return (e.id & 1) == 1; |
---|
886 | } |
---|
887 | |
---|
888 | static Arc direct(Edge e, bool d) { |
---|
889 | return Arc(e.id * 2 + (d ? 1 : 0)); |
---|
890 | } |
---|
891 | |
---|
892 | void first(Node& node) const { |
---|
893 | node.id = first_node; |
---|
894 | } |
---|
895 | |
---|
896 | void next(Node& node) const { |
---|
897 | node.id = nodes[node.id].next; |
---|
898 | } |
---|
899 | |
---|
900 | void first(Arc& e) const { |
---|
901 | int n = first_node; |
---|
902 | while (n != -1 && nodes[n].first_out == -1) { |
---|
903 | n = nodes[n].next; |
---|
904 | } |
---|
905 | e.id = (n == -1) ? -1 : nodes[n].first_out; |
---|
906 | } |
---|
907 | |
---|
908 | void next(Arc& e) const { |
---|
909 | if (arcs[e.id].next_out != -1) { |
---|
910 | e.id = arcs[e.id].next_out; |
---|
911 | } else { |
---|
912 | int n = nodes[arcs[e.id ^ 1].target].next; |
---|
913 | while(n != -1 && nodes[n].first_out == -1) { |
---|
914 | n = nodes[n].next; |
---|
915 | } |
---|
916 | e.id = (n == -1) ? -1 : nodes[n].first_out; |
---|
917 | } |
---|
918 | } |
---|
919 | |
---|
920 | void first(Edge& e) const { |
---|
921 | int n = first_node; |
---|
922 | while (n != -1) { |
---|
923 | e.id = nodes[n].first_out; |
---|
924 | while ((e.id & 1) != 1) { |
---|
925 | e.id = arcs[e.id].next_out; |
---|
926 | } |
---|
927 | if (e.id != -1) { |
---|
928 | e.id /= 2; |
---|
929 | return; |
---|
930 | } |
---|
931 | n = nodes[n].next; |
---|
932 | } |
---|
933 | e.id = -1; |
---|
934 | } |
---|
935 | |
---|
936 | void next(Edge& e) const { |
---|
937 | int n = arcs[e.id * 2].target; |
---|
938 | e.id = arcs[(e.id * 2) | 1].next_out; |
---|
939 | while ((e.id & 1) != 1) { |
---|
940 | e.id = arcs[e.id].next_out; |
---|
941 | } |
---|
942 | if (e.id != -1) { |
---|
943 | e.id /= 2; |
---|
944 | return; |
---|
945 | } |
---|
946 | n = nodes[n].next; |
---|
947 | while (n != -1) { |
---|
948 | e.id = nodes[n].first_out; |
---|
949 | while ((e.id & 1) != 1) { |
---|
950 | e.id = arcs[e.id].next_out; |
---|
951 | } |
---|
952 | if (e.id != -1) { |
---|
953 | e.id /= 2; |
---|
954 | return; |
---|
955 | } |
---|
956 | n = nodes[n].next; |
---|
957 | } |
---|
958 | e.id = -1; |
---|
959 | } |
---|
960 | |
---|
961 | void firstOut(Arc &e, const Node& v) const { |
---|
962 | e.id = nodes[v.id].first_out; |
---|
963 | } |
---|
964 | void nextOut(Arc &e) const { |
---|
965 | e.id = arcs[e.id].next_out; |
---|
966 | } |
---|
967 | |
---|
968 | void firstIn(Arc &e, const Node& v) const { |
---|
969 | e.id = ((nodes[v.id].first_out) ^ 1); |
---|
970 | if (e.id == -2) e.id = -1; |
---|
971 | } |
---|
972 | void nextIn(Arc &e) const { |
---|
973 | e.id = ((arcs[e.id ^ 1].next_out) ^ 1); |
---|
974 | if (e.id == -2) e.id = -1; |
---|
975 | } |
---|
976 | |
---|
977 | void firstInc(Edge &e, bool& d, const Node& v) const { |
---|
978 | int a = nodes[v.id].first_out; |
---|
979 | if (a != -1 ) { |
---|
980 | e.id = a / 2; |
---|
981 | d = ((a & 1) == 1); |
---|
982 | } else { |
---|
983 | e.id = -1; |
---|
984 | d = true; |
---|
985 | } |
---|
986 | } |
---|
987 | void nextInc(Edge &e, bool& d) const { |
---|
988 | int a = (arcs[(e.id * 2) | (d ? 1 : 0)].next_out); |
---|
989 | if (a != -1 ) { |
---|
990 | e.id = a / 2; |
---|
991 | d = ((a & 1) == 1); |
---|
992 | } else { |
---|
993 | e.id = -1; |
---|
994 | d = true; |
---|
995 | } |
---|
996 | } |
---|
997 | |
---|
998 | static int id(Node v) { return v.id; } |
---|
999 | static int id(Arc e) { return e.id; } |
---|
1000 | static int id(Edge e) { return e.id; } |
---|
1001 | |
---|
1002 | static Node nodeFromId(int id) { return Node(id);} |
---|
1003 | static Arc arcFromId(int id) { return Arc(id);} |
---|
1004 | static Edge edgeFromId(int id) { return Edge(id);} |
---|
1005 | |
---|
1006 | bool valid(Node n) const { |
---|
1007 | return n.id >= 0 && n.id < static_cast<int>(nodes.size()) && |
---|
1008 | nodes[n.id].prev != -2; |
---|
1009 | } |
---|
1010 | |
---|
1011 | bool valid(Arc a) const { |
---|
1012 | return a.id >= 0 && a.id < static_cast<int>(arcs.size()) && |
---|
1013 | arcs[a.id].prev_out != -2; |
---|
1014 | } |
---|
1015 | |
---|
1016 | bool valid(Edge e) const { |
---|
1017 | return e.id >= 0 && 2 * e.id < static_cast<int>(arcs.size()) && |
---|
1018 | arcs[2 * e.id].prev_out != -2; |
---|
1019 | } |
---|
1020 | |
---|
1021 | Node addNode() { |
---|
1022 | int n; |
---|
1023 | |
---|
1024 | if(first_free_node==-1) { |
---|
1025 | n = nodes.size(); |
---|
1026 | nodes.push_back(NodeT()); |
---|
1027 | } else { |
---|
1028 | n = first_free_node; |
---|
1029 | first_free_node = nodes[n].next; |
---|
1030 | } |
---|
1031 | |
---|
1032 | nodes[n].next = first_node; |
---|
1033 | if (first_node != -1) nodes[first_node].prev = n; |
---|
1034 | first_node = n; |
---|
1035 | nodes[n].prev = -1; |
---|
1036 | |
---|
1037 | nodes[n].first_out = -1; |
---|
1038 | |
---|
1039 | return Node(n); |
---|
1040 | } |
---|
1041 | |
---|
1042 | Edge addEdge(Node u, Node v) { |
---|
1043 | int n; |
---|
1044 | |
---|
1045 | if (first_free_arc == -1) { |
---|
1046 | n = arcs.size(); |
---|
1047 | arcs.push_back(ArcT()); |
---|
1048 | arcs.push_back(ArcT()); |
---|
1049 | } else { |
---|
1050 | n = first_free_arc; |
---|
1051 | first_free_arc = arcs[n].next_out; |
---|
1052 | } |
---|
1053 | |
---|
1054 | arcs[n].target = u.id; |
---|
1055 | arcs[n | 1].target = v.id; |
---|
1056 | |
---|
1057 | arcs[n].next_out = nodes[v.id].first_out; |
---|
1058 | if (nodes[v.id].first_out != -1) { |
---|
1059 | arcs[nodes[v.id].first_out].prev_out = n; |
---|
1060 | } |
---|
1061 | arcs[n].prev_out = -1; |
---|
1062 | nodes[v.id].first_out = n; |
---|
1063 | |
---|
1064 | arcs[n | 1].next_out = nodes[u.id].first_out; |
---|
1065 | if (nodes[u.id].first_out != -1) { |
---|
1066 | arcs[nodes[u.id].first_out].prev_out = (n | 1); |
---|
1067 | } |
---|
1068 | arcs[n | 1].prev_out = -1; |
---|
1069 | nodes[u.id].first_out = (n | 1); |
---|
1070 | |
---|
1071 | return Edge(n / 2); |
---|
1072 | } |
---|
1073 | |
---|
1074 | void erase(const Node& node) { |
---|
1075 | int n = node.id; |
---|
1076 | |
---|
1077 | if(nodes[n].next != -1) { |
---|
1078 | nodes[nodes[n].next].prev = nodes[n].prev; |
---|
1079 | } |
---|
1080 | |
---|
1081 | if(nodes[n].prev != -1) { |
---|
1082 | nodes[nodes[n].prev].next = nodes[n].next; |
---|
1083 | } else { |
---|
1084 | first_node = nodes[n].next; |
---|
1085 | } |
---|
1086 | |
---|
1087 | nodes[n].next = first_free_node; |
---|
1088 | first_free_node = n; |
---|
1089 | nodes[n].prev = -2; |
---|
1090 | } |
---|
1091 | |
---|
1092 | void erase(const Edge& edge) { |
---|
1093 | int n = edge.id * 2; |
---|
1094 | |
---|
1095 | if (arcs[n].next_out != -1) { |
---|
1096 | arcs[arcs[n].next_out].prev_out = arcs[n].prev_out; |
---|
1097 | } |
---|
1098 | |
---|
1099 | if (arcs[n].prev_out != -1) { |
---|
1100 | arcs[arcs[n].prev_out].next_out = arcs[n].next_out; |
---|
1101 | } else { |
---|
1102 | nodes[arcs[n | 1].target].first_out = arcs[n].next_out; |
---|
1103 | } |
---|
1104 | |
---|
1105 | if (arcs[n | 1].next_out != -1) { |
---|
1106 | arcs[arcs[n | 1].next_out].prev_out = arcs[n | 1].prev_out; |
---|
1107 | } |
---|
1108 | |
---|
1109 | if (arcs[n | 1].prev_out != -1) { |
---|
1110 | arcs[arcs[n | 1].prev_out].next_out = arcs[n | 1].next_out; |
---|
1111 | } else { |
---|
1112 | nodes[arcs[n].target].first_out = arcs[n | 1].next_out; |
---|
1113 | } |
---|
1114 | |
---|
1115 | arcs[n].next_out = first_free_arc; |
---|
1116 | first_free_arc = n; |
---|
1117 | arcs[n].prev_out = -2; |
---|
1118 | arcs[n | 1].prev_out = -2; |
---|
1119 | |
---|
1120 | } |
---|
1121 | |
---|
1122 | void clear() { |
---|
1123 | arcs.clear(); |
---|
1124 | nodes.clear(); |
---|
1125 | first_node = first_free_node = first_free_arc = -1; |
---|
1126 | } |
---|
1127 | |
---|
1128 | protected: |
---|
1129 | |
---|
1130 | void changeV(Edge e, Node n) { |
---|
1131 | if(arcs[2 * e.id].next_out != -1) { |
---|
1132 | arcs[arcs[2 * e.id].next_out].prev_out = arcs[2 * e.id].prev_out; |
---|
1133 | } |
---|
1134 | if(arcs[2 * e.id].prev_out != -1) { |
---|
1135 | arcs[arcs[2 * e.id].prev_out].next_out = |
---|
1136 | arcs[2 * e.id].next_out; |
---|
1137 | } else { |
---|
1138 | nodes[arcs[(2 * e.id) | 1].target].first_out = |
---|
1139 | arcs[2 * e.id].next_out; |
---|
1140 | } |
---|
1141 | |
---|
1142 | if (nodes[n.id].first_out != -1) { |
---|
1143 | arcs[nodes[n.id].first_out].prev_out = 2 * e.id; |
---|
1144 | } |
---|
1145 | arcs[(2 * e.id) | 1].target = n.id; |
---|
1146 | arcs[2 * e.id].prev_out = -1; |
---|
1147 | arcs[2 * e.id].next_out = nodes[n.id].first_out; |
---|
1148 | nodes[n.id].first_out = 2 * e.id; |
---|
1149 | } |
---|
1150 | |
---|
1151 | void changeU(Edge e, Node n) { |
---|
1152 | if(arcs[(2 * e.id) | 1].next_out != -1) { |
---|
1153 | arcs[arcs[(2 * e.id) | 1].next_out].prev_out = |
---|
1154 | arcs[(2 * e.id) | 1].prev_out; |
---|
1155 | } |
---|
1156 | if(arcs[(2 * e.id) | 1].prev_out != -1) { |
---|
1157 | arcs[arcs[(2 * e.id) | 1].prev_out].next_out = |
---|
1158 | arcs[(2 * e.id) | 1].next_out; |
---|
1159 | } else { |
---|
1160 | nodes[arcs[2 * e.id].target].first_out = |
---|
1161 | arcs[(2 * e.id) | 1].next_out; |
---|
1162 | } |
---|
1163 | |
---|
1164 | if (nodes[n.id].first_out != -1) { |
---|
1165 | arcs[nodes[n.id].first_out].prev_out = ((2 * e.id) | 1); |
---|
1166 | } |
---|
1167 | arcs[2 * e.id].target = n.id; |
---|
1168 | arcs[(2 * e.id) | 1].prev_out = -1; |
---|
1169 | arcs[(2 * e.id) | 1].next_out = nodes[n.id].first_out; |
---|
1170 | nodes[n.id].first_out = ((2 * e.id) | 1); |
---|
1171 | } |
---|
1172 | |
---|
1173 | }; |
---|
1174 | |
---|
1175 | typedef GraphExtender<ListGraphBase> ExtendedListGraphBase; |
---|
1176 | |
---|
1177 | |
---|
1178 | /// \addtogroup graphs |
---|
1179 | /// @{ |
---|
1180 | |
---|
1181 | ///A general undirected graph structure. |
---|
1182 | |
---|
1183 | ///\ref ListGraph is a versatile and fast undirected graph |
---|
1184 | ///implementation based on linked lists that are stored in |
---|
1185 | ///\c std::vector structures. |
---|
1186 | /// |
---|
1187 | ///This type fully conforms to the \ref concepts::Graph "Graph concept" |
---|
1188 | ///and it also provides several useful additional functionalities. |
---|
1189 | ///Most of its member functions and nested classes are documented |
---|
1190 | ///only in the concept class. |
---|
1191 | /// |
---|
1192 | ///This class provides only linear time counting for nodes, edges and arcs. |
---|
1193 | /// |
---|
1194 | ///\sa concepts::Graph |
---|
1195 | ///\sa ListDigraph |
---|
1196 | class ListGraph : public ExtendedListGraphBase { |
---|
1197 | typedef ExtendedListGraphBase Parent; |
---|
1198 | |
---|
1199 | private: |
---|
1200 | /// Graphs are \e not copy constructible. Use GraphCopy instead. |
---|
1201 | ListGraph(const ListGraph &) :ExtendedListGraphBase() {}; |
---|
1202 | /// \brief Assignment of a graph to another one is \e not allowed. |
---|
1203 | /// Use GraphCopy instead. |
---|
1204 | void operator=(const ListGraph &) {} |
---|
1205 | public: |
---|
1206 | /// Constructor |
---|
1207 | |
---|
1208 | /// Constructor. |
---|
1209 | /// |
---|
1210 | ListGraph() {} |
---|
1211 | |
---|
1212 | typedef Parent::OutArcIt IncEdgeIt; |
---|
1213 | |
---|
1214 | /// \brief Add a new node to the graph. |
---|
1215 | /// |
---|
1216 | /// This function adds a new node to the graph. |
---|
1217 | /// \return The new node. |
---|
1218 | Node addNode() { return Parent::addNode(); } |
---|
1219 | |
---|
1220 | /// \brief Add a new edge to the graph. |
---|
1221 | /// |
---|
1222 | /// This function adds a new edge to the graph between nodes |
---|
1223 | /// \c u and \c v with inherent orientation from node \c u to |
---|
1224 | /// node \c v. |
---|
1225 | /// \return The new edge. |
---|
1226 | Edge addEdge(Node u, Node v) { |
---|
1227 | return Parent::addEdge(u, v); |
---|
1228 | } |
---|
1229 | |
---|
1230 | ///\brief Erase a node from the graph. |
---|
1231 | /// |
---|
1232 | /// This function erases the given node along with its incident arcs |
---|
1233 | /// from the graph. |
---|
1234 | /// |
---|
1235 | /// \note All iterators referencing the removed node or the incident |
---|
1236 | /// edges are invalidated, of course. |
---|
1237 | void erase(Node n) { Parent::erase(n); } |
---|
1238 | |
---|
1239 | ///\brief Erase an edge from the graph. |
---|
1240 | /// |
---|
1241 | /// This function erases the given edge from the graph. |
---|
1242 | /// |
---|
1243 | /// \note All iterators referencing the removed edge are invalidated, |
---|
1244 | /// of course. |
---|
1245 | void erase(Edge e) { Parent::erase(e); } |
---|
1246 | /// Node validity check |
---|
1247 | |
---|
1248 | /// This function gives back \c true if the given node is valid, |
---|
1249 | /// i.e. it is a real node of the graph. |
---|
1250 | /// |
---|
1251 | /// \warning A removed node could become valid again if new nodes are |
---|
1252 | /// added to the graph. |
---|
1253 | bool valid(Node n) const { return Parent::valid(n); } |
---|
1254 | /// Edge validity check |
---|
1255 | |
---|
1256 | /// This function gives back \c true if the given edge is valid, |
---|
1257 | /// i.e. it is a real edge of the graph. |
---|
1258 | /// |
---|
1259 | /// \warning A removed edge could become valid again if new edges are |
---|
1260 | /// added to the graph. |
---|
1261 | bool valid(Edge e) const { return Parent::valid(e); } |
---|
1262 | /// Arc validity check |
---|
1263 | |
---|
1264 | /// This function gives back \c true if the given arc is valid, |
---|
1265 | /// i.e. it is a real arc of the graph. |
---|
1266 | /// |
---|
1267 | /// \warning A removed arc could become valid again if new edges are |
---|
1268 | /// added to the graph. |
---|
1269 | bool valid(Arc a) const { return Parent::valid(a); } |
---|
1270 | |
---|
1271 | /// \brief Change the first node of an edge. |
---|
1272 | /// |
---|
1273 | /// This function changes the first node of the given edge \c e to \c n. |
---|
1274 | /// |
---|
1275 | ///\note \c EdgeIt and \c ArcIt iterators referencing the |
---|
1276 | ///changed edge are invalidated and all other iterators whose |
---|
1277 | ///base node is the changed node are also invalidated. |
---|
1278 | /// |
---|
1279 | ///\warning This functionality cannot be used together with the |
---|
1280 | ///Snapshot feature. |
---|
1281 | void changeU(Edge e, Node n) { |
---|
1282 | Parent::changeU(e,n); |
---|
1283 | } |
---|
1284 | /// \brief Change the second node of an edge. |
---|
1285 | /// |
---|
1286 | /// This function changes the second node of the given edge \c e to \c n. |
---|
1287 | /// |
---|
1288 | ///\note \c EdgeIt iterators referencing the changed edge remain |
---|
1289 | ///valid, but \c ArcIt iterators referencing the changed edge and |
---|
1290 | ///all other iterators whose base node is the changed node are also |
---|
1291 | ///invalidated. |
---|
1292 | /// |
---|
1293 | ///\warning This functionality cannot be used together with the |
---|
1294 | ///Snapshot feature. |
---|
1295 | void changeV(Edge e, Node n) { |
---|
1296 | Parent::changeV(e,n); |
---|
1297 | } |
---|
1298 | |
---|
1299 | /// \brief Contract two nodes. |
---|
1300 | /// |
---|
1301 | /// This function contracts the given two nodes. |
---|
1302 | /// Node \c b is removed, but instead of deleting |
---|
1303 | /// its incident edges, they are joined to node \c a. |
---|
1304 | /// If the last parameter \c r is \c true (this is the default value), |
---|
1305 | /// then the newly created loops are removed. |
---|
1306 | /// |
---|
1307 | /// \note The moved edges are joined to node \c a using changeU() |
---|
1308 | /// or changeV(), thus all edge and arc iterators whose base node is |
---|
1309 | /// \c b are invalidated. |
---|
1310 | /// Moreover all iterators referencing node \c b or the removed |
---|
1311 | /// loops are also invalidated. Other iterators remain valid. |
---|
1312 | /// |
---|
1313 | ///\warning This functionality cannot be used together with the |
---|
1314 | ///Snapshot feature. |
---|
1315 | void contract(Node a, Node b, bool r = true) { |
---|
1316 | for(IncEdgeIt e(*this, b); e!=INVALID;) { |
---|
1317 | IncEdgeIt f = e; ++f; |
---|
1318 | if (r && runningNode(e) == a) { |
---|
1319 | erase(e); |
---|
1320 | } else if (u(e) == b) { |
---|
1321 | changeU(e, a); |
---|
1322 | } else { |
---|
1323 | changeV(e, a); |
---|
1324 | } |
---|
1325 | e = f; |
---|
1326 | } |
---|
1327 | erase(b); |
---|
1328 | } |
---|
1329 | |
---|
1330 | ///Clear the graph. |
---|
1331 | |
---|
1332 | ///This function erases all nodes and arcs from the graph. |
---|
1333 | /// |
---|
1334 | ///\note All iterators of the graph are invalidated, of course. |
---|
1335 | void clear() { |
---|
1336 | Parent::clear(); |
---|
1337 | } |
---|
1338 | |
---|
1339 | /// Reserve memory for nodes. |
---|
1340 | |
---|
1341 | /// Using this function, it is possible to avoid superfluous memory |
---|
1342 | /// allocation: if you know that the graph you want to build will |
---|
1343 | /// be large (e.g. it will contain millions of nodes and/or edges), |
---|
1344 | /// then it is worth reserving space for this amount before starting |
---|
1345 | /// to build the graph. |
---|
1346 | /// \sa reserveEdge() |
---|
1347 | void reserveNode(int n) { nodes.reserve(n); }; |
---|
1348 | |
---|
1349 | /// Reserve memory for edges. |
---|
1350 | |
---|
1351 | /// Using this function, it is possible to avoid superfluous memory |
---|
1352 | /// allocation: if you know that the graph you want to build will |
---|
1353 | /// be large (e.g. it will contain millions of nodes and/or edges), |
---|
1354 | /// then it is worth reserving space for this amount before starting |
---|
1355 | /// to build the graph. |
---|
1356 | /// \sa reserveNode() |
---|
1357 | void reserveEdge(int m) { arcs.reserve(2 * m); }; |
---|
1358 | |
---|
1359 | /// \brief Class to make a snapshot of the graph and restore |
---|
1360 | /// it later. |
---|
1361 | /// |
---|
1362 | /// Class to make a snapshot of the graph and restore it later. |
---|
1363 | /// |
---|
1364 | /// The newly added nodes and edges can be removed |
---|
1365 | /// using the restore() function. |
---|
1366 | /// |
---|
1367 | /// \note After a state is restored, you cannot restore a later state, |
---|
1368 | /// i.e. you cannot add the removed nodes and edges again using |
---|
1369 | /// another Snapshot instance. |
---|
1370 | /// |
---|
1371 | /// \warning Node and edge deletions and other modifications |
---|
1372 | /// (e.g. changing the end-nodes of edges or contracting nodes) |
---|
1373 | /// cannot be restored. These events invalidate the snapshot. |
---|
1374 | /// However, the edges and nodes that were added to the graph after |
---|
1375 | /// making the current snapshot can be removed without invalidating it. |
---|
1376 | class Snapshot { |
---|
1377 | protected: |
---|
1378 | |
---|
1379 | typedef Parent::NodeNotifier NodeNotifier; |
---|
1380 | |
---|
1381 | class NodeObserverProxy : public NodeNotifier::ObserverBase { |
---|
1382 | public: |
---|
1383 | |
---|
1384 | NodeObserverProxy(Snapshot& _snapshot) |
---|
1385 | : snapshot(_snapshot) {} |
---|
1386 | |
---|
1387 | using NodeNotifier::ObserverBase::attach; |
---|
1388 | using NodeNotifier::ObserverBase::detach; |
---|
1389 | using NodeNotifier::ObserverBase::attached; |
---|
1390 | |
---|
1391 | protected: |
---|
1392 | |
---|
1393 | virtual void add(const Node& node) { |
---|
1394 | snapshot.addNode(node); |
---|
1395 | } |
---|
1396 | virtual void add(const std::vector<Node>& nodes) { |
---|
1397 | for (int i = nodes.size() - 1; i >= 0; --i) { |
---|
1398 | snapshot.addNode(nodes[i]); |
---|
1399 | } |
---|
1400 | } |
---|
1401 | virtual void erase(const Node& node) { |
---|
1402 | snapshot.eraseNode(node); |
---|
1403 | } |
---|
1404 | virtual void erase(const std::vector<Node>& nodes) { |
---|
1405 | for (int i = 0; i < int(nodes.size()); ++i) { |
---|
1406 | snapshot.eraseNode(nodes[i]); |
---|
1407 | } |
---|
1408 | } |
---|
1409 | virtual void build() { |
---|
1410 | Node node; |
---|
1411 | std::vector<Node> nodes; |
---|
1412 | for (notifier()->first(node); node != INVALID; |
---|
1413 | notifier()->next(node)) { |
---|
1414 | nodes.push_back(node); |
---|
1415 | } |
---|
1416 | for (int i = nodes.size() - 1; i >= 0; --i) { |
---|
1417 | snapshot.addNode(nodes[i]); |
---|
1418 | } |
---|
1419 | } |
---|
1420 | virtual void clear() { |
---|
1421 | Node node; |
---|
1422 | for (notifier()->first(node); node != INVALID; |
---|
1423 | notifier()->next(node)) { |
---|
1424 | snapshot.eraseNode(node); |
---|
1425 | } |
---|
1426 | } |
---|
1427 | |
---|
1428 | Snapshot& snapshot; |
---|
1429 | }; |
---|
1430 | |
---|
1431 | class EdgeObserverProxy : public EdgeNotifier::ObserverBase { |
---|
1432 | public: |
---|
1433 | |
---|
1434 | EdgeObserverProxy(Snapshot& _snapshot) |
---|
1435 | : snapshot(_snapshot) {} |
---|
1436 | |
---|
1437 | using EdgeNotifier::ObserverBase::attach; |
---|
1438 | using EdgeNotifier::ObserverBase::detach; |
---|
1439 | using EdgeNotifier::ObserverBase::attached; |
---|
1440 | |
---|
1441 | protected: |
---|
1442 | |
---|
1443 | virtual void add(const Edge& edge) { |
---|
1444 | snapshot.addEdge(edge); |
---|
1445 | } |
---|
1446 | virtual void add(const std::vector<Edge>& edges) { |
---|
1447 | for (int i = edges.size() - 1; i >= 0; --i) { |
---|
1448 | snapshot.addEdge(edges[i]); |
---|
1449 | } |
---|
1450 | } |
---|
1451 | virtual void erase(const Edge& edge) { |
---|
1452 | snapshot.eraseEdge(edge); |
---|
1453 | } |
---|
1454 | virtual void erase(const std::vector<Edge>& edges) { |
---|
1455 | for (int i = 0; i < int(edges.size()); ++i) { |
---|
1456 | snapshot.eraseEdge(edges[i]); |
---|
1457 | } |
---|
1458 | } |
---|
1459 | virtual void build() { |
---|
1460 | Edge edge; |
---|
1461 | std::vector<Edge> edges; |
---|
1462 | for (notifier()->first(edge); edge != INVALID; |
---|
1463 | notifier()->next(edge)) { |
---|
1464 | edges.push_back(edge); |
---|
1465 | } |
---|
1466 | for (int i = edges.size() - 1; i >= 0; --i) { |
---|
1467 | snapshot.addEdge(edges[i]); |
---|
1468 | } |
---|
1469 | } |
---|
1470 | virtual void clear() { |
---|
1471 | Edge edge; |
---|
1472 | for (notifier()->first(edge); edge != INVALID; |
---|
1473 | notifier()->next(edge)) { |
---|
1474 | snapshot.eraseEdge(edge); |
---|
1475 | } |
---|
1476 | } |
---|
1477 | |
---|
1478 | Snapshot& snapshot; |
---|
1479 | }; |
---|
1480 | |
---|
1481 | ListGraph *graph; |
---|
1482 | |
---|
1483 | NodeObserverProxy node_observer_proxy; |
---|
1484 | EdgeObserverProxy edge_observer_proxy; |
---|
1485 | |
---|
1486 | std::list<Node> added_nodes; |
---|
1487 | std::list<Edge> added_edges; |
---|
1488 | |
---|
1489 | |
---|
1490 | void addNode(const Node& node) { |
---|
1491 | added_nodes.push_front(node); |
---|
1492 | } |
---|
1493 | void eraseNode(const Node& node) { |
---|
1494 | std::list<Node>::iterator it = |
---|
1495 | std::find(added_nodes.begin(), added_nodes.end(), node); |
---|
1496 | if (it == added_nodes.end()) { |
---|
1497 | clear(); |
---|
1498 | edge_observer_proxy.detach(); |
---|
1499 | throw NodeNotifier::ImmediateDetach(); |
---|
1500 | } else { |
---|
1501 | added_nodes.erase(it); |
---|
1502 | } |
---|
1503 | } |
---|
1504 | |
---|
1505 | void addEdge(const Edge& edge) { |
---|
1506 | added_edges.push_front(edge); |
---|
1507 | } |
---|
1508 | void eraseEdge(const Edge& edge) { |
---|
1509 | std::list<Edge>::iterator it = |
---|
1510 | std::find(added_edges.begin(), added_edges.end(), edge); |
---|
1511 | if (it == added_edges.end()) { |
---|
1512 | clear(); |
---|
1513 | node_observer_proxy.detach(); |
---|
1514 | throw EdgeNotifier::ImmediateDetach(); |
---|
1515 | } else { |
---|
1516 | added_edges.erase(it); |
---|
1517 | } |
---|
1518 | } |
---|
1519 | |
---|
1520 | void attach(ListGraph &_graph) { |
---|
1521 | graph = &_graph; |
---|
1522 | node_observer_proxy.attach(graph->notifier(Node())); |
---|
1523 | edge_observer_proxy.attach(graph->notifier(Edge())); |
---|
1524 | } |
---|
1525 | |
---|
1526 | void detach() { |
---|
1527 | node_observer_proxy.detach(); |
---|
1528 | edge_observer_proxy.detach(); |
---|
1529 | } |
---|
1530 | |
---|
1531 | bool attached() const { |
---|
1532 | return node_observer_proxy.attached(); |
---|
1533 | } |
---|
1534 | |
---|
1535 | void clear() { |
---|
1536 | added_nodes.clear(); |
---|
1537 | added_edges.clear(); |
---|
1538 | } |
---|
1539 | |
---|
1540 | public: |
---|
1541 | |
---|
1542 | /// \brief Default constructor. |
---|
1543 | /// |
---|
1544 | /// Default constructor. |
---|
1545 | /// You have to call save() to actually make a snapshot. |
---|
1546 | Snapshot() |
---|
1547 | : graph(0), node_observer_proxy(*this), |
---|
1548 | edge_observer_proxy(*this) {} |
---|
1549 | |
---|
1550 | /// \brief Constructor that immediately makes a snapshot. |
---|
1551 | /// |
---|
1552 | /// This constructor immediately makes a snapshot of the given graph. |
---|
1553 | Snapshot(ListGraph &gr) |
---|
1554 | : node_observer_proxy(*this), |
---|
1555 | edge_observer_proxy(*this) { |
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1556 | attach(gr); |
---|
1557 | } |
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1558 | |
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1559 | /// \brief Make a snapshot. |
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1560 | /// |
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1561 | /// This function makes a snapshot of the given graph. |
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1562 | /// It can be called more than once. In case of a repeated |
---|
1563 | /// call, the previous snapshot gets lost. |
---|
1564 | void save(ListGraph &gr) { |
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1565 | if (attached()) { |
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1566 | detach(); |
---|
1567 | clear(); |
---|
1568 | } |
---|
1569 | attach(gr); |
---|
1570 | } |
---|
1571 | |
---|
1572 | /// \brief Undo the changes until the last snapshot. |
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1573 | /// |
---|
1574 | /// This function undos the changes until the last snapshot |
---|
1575 | /// created by save() or Snapshot(ListGraph&). |
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1576 | /// |
---|
1577 | /// \warning This method invalidates the snapshot, i.e. repeated |
---|
1578 | /// restoring is not supported unless you call save() again. |
---|
1579 | void restore() { |
---|
1580 | detach(); |
---|
1581 | for(std::list<Edge>::iterator it = added_edges.begin(); |
---|
1582 | it != added_edges.end(); ++it) { |
---|
1583 | graph->erase(*it); |
---|
1584 | } |
---|
1585 | for(std::list<Node>::iterator it = added_nodes.begin(); |
---|
1586 | it != added_nodes.end(); ++it) { |
---|
1587 | graph->erase(*it); |
---|
1588 | } |
---|
1589 | clear(); |
---|
1590 | } |
---|
1591 | |
---|
1592 | /// \brief Returns \c true if the snapshot is valid. |
---|
1593 | /// |
---|
1594 | /// This function returns \c true if the snapshot is valid. |
---|
1595 | bool valid() const { |
---|
1596 | return attached(); |
---|
1597 | } |
---|
1598 | }; |
---|
1599 | }; |
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1600 | |
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1601 | /// @} |
---|
1602 | } //namespace lemon |
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1603 | |
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1604 | |
---|
1605 | #endif |
---|