1 | #include <iostream> |
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2 | |
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3 | #include <smart_graph.h> |
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4 | #include <dimacs.h> |
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5 | #include <preflow.h> |
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6 | #include <time_measure.h> |
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7 | |
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8 | using namespace hugo; |
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9 | |
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10 | int main(int, char **) { |
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11 | |
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12 | typedef SmartGraph Graph; |
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13 | |
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14 | typedef Graph::Node Node; |
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15 | typedef Graph::EdgeIt EdgeIt; |
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16 | |
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17 | Graph G; |
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18 | Node s, t; |
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19 | Graph::EdgeMap<int> cap(G); |
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20 | readDimacsMaxFlow(std::cin, G, s, t, cap); |
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21 | Timer ts; |
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22 | |
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23 | std::cout << |
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24 | "\n Testing preflow.h on a graph with " << |
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25 | G.nodeNum() << " nodes and " << G.edgeNum() << " edges..." |
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26 | << std::endl; |
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27 | |
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28 | |
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29 | Graph::EdgeMap<int> flow(G,0); |
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30 | Preflow<Graph, int> preflow_test(G, s, t, cap, flow); |
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31 | std::cout << "\nCalling run() (flow must be constant zero)..."<<std::endl; |
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32 | ts.reset(); |
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33 | preflow_test.run(); |
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34 | std::cout << "Elapsed time: " << ts << std::endl; |
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35 | |
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36 | Graph::NodeMap<bool> mincut(G); |
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37 | preflow_test.minMinCut(mincut); |
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38 | int min_min_cut_value=0; |
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39 | Graph::NodeMap<bool> cut(G); |
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40 | preflow_test.minCut(cut); |
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41 | int min_cut_value=0; |
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42 | Graph::NodeMap<bool> maxcut(G); |
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43 | preflow_test.maxMinCut(maxcut); |
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44 | int max_min_cut_value=0; |
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45 | EdgeIt e; |
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46 | for(G.first(e); G.valid(e); G.next(e)) { |
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47 | int c=cap[e]; |
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48 | if (mincut[G.tail(e)] && !mincut[G.head(e)]) min_min_cut_value+=c; |
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49 | if (cut[G.tail(e)] && !cut[G.head(e)]) min_cut_value+=c; |
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50 | if (maxcut[G.tail(e)] && !maxcut[G.head(e)]) max_min_cut_value+=c; |
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51 | } |
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52 | |
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53 | std::cout << "\nChecking the result: " <<std::endl; |
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54 | std::cout << "Flow value: "<< preflow_test.flowValue() << std::endl; |
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55 | std::cout << "Min cut value: "<< min_cut_value << std::endl; |
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56 | std::cout << "Min min cut value: "<< min_min_cut_value << std::endl; |
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57 | std::cout << "Max min cut value: "<< max_min_cut_value << |
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58 | std::endl; |
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59 | |
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60 | if ( preflow_test.flowValue() == min_cut_value && |
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61 | min_cut_value == min_min_cut_value && |
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62 | min_min_cut_value == max_min_cut_value ) |
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63 | std::cout << "They are equal. " <<std::endl; |
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64 | |
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65 | |
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66 | |
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67 | |
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68 | |
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69 | Preflow<Graph, int> preflow_test2(G, s, t, cap, flow); |
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70 | std::cout << "\n\nCalling preflow(GEN_FLOW) with the given maximum flow..."<<std::endl; |
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71 | ts.reset(); |
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72 | preflow_test2.preflow(preflow_test2.GEN_FLOW); |
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73 | std::cout << "Elapsed time: " << ts << std::endl; |
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74 | |
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75 | Graph::NodeMap<bool> mincut2(G); |
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76 | preflow_test.minMinCut(mincut2); |
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77 | int min_min_cut2_value=0; |
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78 | Graph::NodeMap<bool> cut2(G); |
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79 | preflow_test.minCut(cut2); |
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80 | int min_cut2_value=0; |
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81 | Graph::NodeMap<bool> maxcut2(G); |
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82 | preflow_test.maxMinCut(maxcut2); |
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83 | int max_min_cut2_value=0; |
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84 | for(G.first(e); G.valid(e); G.next(e)) { |
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85 | int c=cap[e]; |
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86 | if (mincut2[G.tail(e)] && !mincut2[G.head(e)]) min_min_cut2_value+=c; |
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87 | if (cut2[G.tail(e)] && !cut2[G.head(e)]) min_cut2_value+=c; |
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88 | if (maxcut2[G.tail(e)] && !maxcut2[G.head(e)]) max_min_cut2_value+=c; |
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89 | } |
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90 | |
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91 | std::cout << "\nThe given flow value is " |
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92 | << preflow_test2.flowValue(); |
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93 | |
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94 | if ( preflow_test2.flowValue() == min_cut2_value && |
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95 | min_cut2_value == min_min_cut2_value && |
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96 | min_min_cut2_value == max_min_cut2_value ) |
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97 | std::cout <<", which is equal to all three min cut values." |
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98 | <<std::endl; |
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99 | |
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100 | |
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101 | |
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102 | |
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103 | |
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104 | Graph::EdgeMap<int> flow3(G,0); |
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105 | Preflow<Graph, int> preflow_test3(G, s, t, cap, flow3); |
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106 | std::cout << "\n\nCalling preflowPhase0(PREFLOW) on the constant zero flow..."<<std::endl; |
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107 | ts.reset(); |
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108 | preflow_test3.preflowPhase0(preflow_test3.PREFLOW); |
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109 | std::cout << "Elapsed time: " << ts << std::endl; |
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110 | Graph::NodeMap<bool> actcut3(G); |
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111 | std::cout << "\nCalling actMinCut()..."<<std::endl; |
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112 | preflow_test3.actMinCut(actcut3); |
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113 | std::cout << "Calling preflowPhase1() on the given flow..."<<std::endl; |
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114 | ts.reset(); |
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115 | preflow_test3.preflowPhase1(); |
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116 | std::cout << "Elapsed time: " << ts << std::endl; |
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117 | |
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118 | int act_min_cut3_value=0; |
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119 | |
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120 | Graph::NodeMap<bool> mincut3(G); |
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121 | preflow_test.minMinCut(mincut3); |
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122 | int min_min_cut3_value=0; |
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123 | |
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124 | Graph::NodeMap<bool> cut3(G); |
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125 | preflow_test.minCut(cut3); |
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126 | int min_cut3_value=0; |
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127 | |
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128 | Graph::NodeMap<bool> maxcut3(G); |
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129 | preflow_test.maxMinCut(maxcut3); |
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130 | int max_min_cut3_value=0; |
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131 | |
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132 | for(G.first(e); G.valid(e); G.next(e)) { |
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133 | int c=cap[e]; |
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134 | if (mincut3[G.tail(e)] && !mincut3[G.head(e)]) min_min_cut3_value+=c; |
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135 | if (cut3[G.tail(e)] && !cut3[G.head(e)]) min_cut3_value+=c; |
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136 | if (maxcut3[G.tail(e)] && !maxcut3[G.head(e)]) max_min_cut3_value+=c; |
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137 | if (actcut3[G.tail(e)] && !actcut3[G.head(e)]) act_min_cut3_value+=c; |
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138 | } |
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139 | |
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140 | std::cout << "\nThe min cut value given by actMinCut() after phase 0 is "<< |
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141 | act_min_cut3_value; |
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142 | |
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143 | if ( preflow_test3.flowValue() == min_cut3_value && |
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144 | min_cut3_value == min_min_cut3_value && |
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145 | min_min_cut3_value == max_min_cut3_value && |
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146 | max_min_cut3_value == act_min_cut3_value ) { |
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147 | std::cout << |
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148 | ", which is equal to the given flow value and to all three min cut values after phase 1." |
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149 | <<std::endl; |
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150 | } |
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151 | |
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152 | |
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153 | |
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154 | |
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155 | |
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156 | Graph::EdgeMap<int> flow4(G,0); |
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157 | Preflow<Graph, int> preflow_test4(G, s, t, cap, flow4); |
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158 | std::cout << |
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159 | "\n\nCalling preflow(PREFLOW) with the constant 0 flow, the result is f..." |
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160 | <<std::endl; |
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161 | preflow_test4.preflow(preflow_test4.PREFLOW); |
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162 | |
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163 | std::cout << "Swapping the source and the target, "<<std::endl; |
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164 | std::cout << "by calling resetSource(t) and resetTarget(s)..." |
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165 | <<std::endl; |
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166 | preflow_test4.resetSource(t); |
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167 | preflow_test4.resetTarget(s); |
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168 | |
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169 | std::cout << |
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170 | "Calling preflow(PREFLOW) to find a maximum t-s flow starting with flow f..." |
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171 | <<std::endl; |
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172 | preflow_test4.preflow(preflow_test4.PREFLOW); |
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173 | |
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174 | Graph::NodeMap<bool> mincut4(G); |
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175 | preflow_test4.minMinCut(mincut4); |
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176 | int min_min_cut4_value=0; |
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177 | Graph::NodeMap<bool> cut4(G); |
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178 | preflow_test4.minCut(cut4); |
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179 | int min_cut4_value=0; |
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180 | Graph::NodeMap<bool> maxcut4(G); |
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181 | preflow_test4.maxMinCut(maxcut4); |
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182 | int max_min_cut4_value=0; |
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183 | for(G.first(e); G.valid(e); G.next(e)) { |
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184 | int c=cap[e]; |
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185 | if (mincut4[G.tail(e)] && !mincut4[G.head(e)]) min_min_cut4_value+=c; |
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186 | if (cut4[G.tail(e)] && !cut4[G.head(e)]) min_cut4_value+=c; |
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187 | if (maxcut4[G.tail(e)] && !maxcut4[G.head(e)]) max_min_cut4_value+=c; |
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188 | } |
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189 | |
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190 | std::cout << "\nThe given flow value is " |
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191 | << preflow_test4.flowValue(); |
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192 | |
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193 | if ( preflow_test4.flowValue() == min_cut4_value && |
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194 | min_cut4_value == min_min_cut4_value && |
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195 | min_min_cut4_value == max_min_cut4_value ) |
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196 | std::cout <<", which is equal to all three min cut values." |
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197 | <<std::endl; |
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198 | |
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199 | |
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200 | |
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201 | |
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202 | Graph::EdgeMap<int> flow5(G,0); |
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203 | std::cout << "Resetting the stored flow to constant zero, by calling resetFlow..." |
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204 | <<std::endl; |
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205 | preflow_test4.resetFlow(flow5); |
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206 | std::cout << |
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207 | "Calling preflow(GEN_FLOW) to find a maximum t-s flow "<<std::endl; |
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208 | std::cout << |
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209 | "starting with this constant zero flow..." <<std::endl; |
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210 | preflow_test4.preflow(preflow_test4.GEN_FLOW); |
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211 | |
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212 | Graph::NodeMap<bool> mincut5(G); |
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213 | preflow_test4.minMinCut(mincut5); |
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214 | int min_min_cut5_value=0; |
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215 | Graph::NodeMap<bool> cut5(G); |
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216 | preflow_test4.minCut(cut5); |
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217 | int min_cut5_value=0; |
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218 | Graph::NodeMap<bool> maxcut5(G); |
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219 | preflow_test4.maxMinCut(maxcut5); |
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220 | int max_min_cut5_value=0; |
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221 | for(G.first(e); G.valid(e); G.next(e)) { |
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222 | int c=cap[e]; |
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223 | if (mincut5[G.tail(e)] && !mincut5[G.head(e)]) min_min_cut5_value+=c; |
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224 | if (cut5[G.tail(e)] && !cut5[G.head(e)]) min_cut5_value+=c; |
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225 | if (maxcut5[G.tail(e)] && !maxcut5[G.head(e)]) max_min_cut5_value+=c; |
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226 | } |
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227 | |
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228 | std::cout << "\nThe given flow value is " |
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229 | << preflow_test4.flowValue(); |
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230 | |
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231 | if ( preflow_test4.flowValue() == min_cut5_value && |
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232 | min_cut5_value == min_min_cut5_value && |
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233 | min_min_cut5_value == max_min_cut5_value ) |
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234 | std::cout <<", which is equal to all three min cut values." |
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235 | <<std::endl<<std::endl; |
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236 | |
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237 | |
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238 | return 0; |
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239 | } |
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