1 | // -*- c++ -*- |
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2 | #include <iostream> |
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3 | #include <fstream> |
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4 | |
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5 | #include <lemon/smart_graph.h> |
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6 | #include <lemon/list_graph.h> |
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7 | #include <lemon/dimacs.h> |
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8 | #include <lemon/time_measure.h> |
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9 | //#include <graph_wrapper.h> |
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10 | #include <lemon/preflow.h> |
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11 | #include <augmenting_flow.h> |
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12 | //#include <preflow_res.h> |
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13 | #include <lp_solver_wrapper.h> |
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14 | #include <min_cost_gen_flow.h> |
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15 | |
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16 | // Use a DIMACS max flow file as stdin. |
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17 | // max_flow_demo < dimacs_max_flow_file |
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18 | |
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19 | using namespace lemon; |
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20 | |
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21 | int main(int, char **) { |
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22 | |
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23 | typedef ListGraph MutableGraph; |
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24 | typedef ListGraph Graph; |
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25 | typedef Graph::Node Node; |
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26 | typedef Graph::Edge Edge; |
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27 | typedef Graph::EdgeIt EdgeIt; |
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28 | |
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29 | Graph g; |
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30 | |
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31 | Node s, t; |
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32 | Graph::EdgeMap<int> cap(g); |
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33 | //readDimacsMaxFlow(std::cin, g, s, t, cap); |
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34 | readDimacs(std::cin, g, cap, s, t); |
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35 | Timer ts; |
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36 | Graph::EdgeMap<int> flow(g); //0 flow |
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37 | Preflow<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> > |
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38 | max_flow_test(g, s, t, cap, flow); |
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39 | AugmentingFlow<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> > |
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40 | augmenting_flow_test(g, s, t, cap, flow); |
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41 | |
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42 | Graph::NodeMap<bool> cut(g); |
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43 | |
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44 | { |
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45 | std::cout << "preflow ..." << std::endl; |
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46 | ts.reset(); |
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47 | max_flow_test.run(); |
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48 | std::cout << "elapsed time: " << ts << std::endl; |
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49 | std::cout << "flow value: "<< max_flow_test.flowValue() << std::endl; |
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50 | max_flow_test.minCut(cut); |
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51 | |
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52 | for (EdgeIt e(g); e!=INVALID; ++e) { |
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53 | if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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54 | std::cout << "Slackness does not hold!" << std::endl; |
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55 | if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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56 | std::cout << "Slackness does not hold!" << std::endl; |
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57 | } |
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58 | } |
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59 | |
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60 | // { |
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61 | // std::cout << "preflow ..." << std::endl; |
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62 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0); |
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63 | // ts.reset(); |
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64 | // max_flow_test.preflow(Preflow<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> >::GEN_FLOW); |
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65 | // std::cout << "elapsed time: " << ts << std::endl; |
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66 | // std::cout << "flow value: "<< max_flow_test.flowValue() << std::endl; |
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67 | |
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68 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) { |
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69 | // if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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70 | // std::cout << "Slackness does not hold!" << std::endl; |
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71 | // if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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72 | // std::cout << "Slackness does not hold!" << std::endl; |
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73 | // } |
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74 | // } |
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75 | |
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76 | // { |
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77 | // std::cout << "wrapped preflow ..." << std::endl; |
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78 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0); |
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79 | // ts.reset(); |
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80 | // pre_flow_res.run(); |
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81 | // std::cout << "elapsed time: " << ts << std::endl; |
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82 | // std::cout << "flow value: "<< pre_flow_test.flowValue() << std::endl; |
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83 | // } |
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84 | |
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85 | { |
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86 | std::cout << "physical blocking flow augmentation ..." << std::endl; |
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87 | for (EdgeIt e(g); e!=INVALID; ++e) flow.set(e, 0); |
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88 | ts.reset(); |
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89 | int i=0; |
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90 | while (augmenting_flow_test.augmentOnBlockingFlow<MutableGraph>()) { ++i; } |
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91 | std::cout << "elapsed time: " << ts << std::endl; |
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92 | std::cout << "number of augmentation phases: " << i << std::endl; |
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93 | std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl; |
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94 | |
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95 | for (EdgeIt e(g); e!=INVALID; ++e) { |
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96 | if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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97 | std::cout << "Slackness does not hold!" << std::endl; |
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98 | if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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99 | std::cout << "Slackness does not hold!" << std::endl; |
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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 | // std::cout << "faster physical blocking flow augmentation ..." << std::endl; |
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105 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0); |
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106 | // ts.reset(); |
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107 | // int i=0; |
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108 | // while (max_flow_test.augmentOnBlockingFlow1<MutableGraph>()) { ++i; } |
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109 | // std::cout << "elapsed time: " << ts << std::endl; |
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110 | // std::cout << "number of augmentation phases: " << i << std::endl; |
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111 | // std::cout << "flow value: "<< max_flow_test.flowValue() << std::endl; |
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112 | // } |
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113 | |
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114 | { |
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115 | std::cout << "on-the-fly blocking flow augmentation ..." << std::endl; |
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116 | for (EdgeIt e(g); e!=INVALID; ++e) flow.set(e, 0); |
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117 | ts.reset(); |
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118 | int i=0; |
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119 | while (augmenting_flow_test.augmentOnBlockingFlow2()) { ++i; } |
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120 | std::cout << "elapsed time: " << ts << std::endl; |
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121 | std::cout << "number of augmentation phases: " << i << std::endl; |
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122 | std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl; |
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123 | |
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124 | for (EdgeIt e(g); e!=INVALID; ++e) { |
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125 | if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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126 | std::cout << "Slackness does not hold!" << std::endl; |
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127 | if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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128 | std::cout << "Slackness does not hold!" << std::endl; |
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129 | } |
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130 | } |
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131 | |
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132 | // { |
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133 | // std::cout << "on-the-fly shortest path augmentation ..." << std::endl; |
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134 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0); |
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135 | // ts.reset(); |
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136 | // int i=0; |
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137 | // while (augmenting_flow_test.augmentOnShortestPath()) { ++i; } |
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138 | // std::cout << "elapsed time: " << ts << std::endl; |
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139 | // std::cout << "number of augmentation phases: " << i << std::endl; |
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140 | // std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl; |
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141 | |
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142 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) { |
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143 | // if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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144 | // std::cout << "Slackness does not hold!" << std::endl; |
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145 | // if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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146 | // std::cout << "Slackness does not hold!" << std::endl; |
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147 | // } |
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148 | // } |
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149 | |
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150 | // { |
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151 | // std::cout << "on-the-fly shortest path augmentation ..." << std::endl; |
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152 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0); |
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153 | // ts.reset(); |
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154 | // int i=0; |
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155 | // while (augmenting_flow_test.augmentOnShortestPath2()) { ++i; } |
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156 | // std::cout << "elapsed time: " << ts << std::endl; |
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157 | // std::cout << "number of augmentation phases: " << i << std::endl; |
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158 | // std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl; |
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159 | |
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160 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) { |
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161 | // if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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162 | // std::cout << "Slackness does not hold!" << std::endl; |
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163 | // if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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164 | // std::cout << "Slackness does not hold!" << std::endl; |
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165 | // } |
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166 | // } |
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167 | |
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168 | ts.reset(); |
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169 | |
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170 | Edge e=g.addEdge(t, s); |
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171 | Graph::EdgeMap<int> cost(g, 0); |
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172 | cost.set(e, -1); |
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173 | cap.set(e, 10000); |
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174 | typedef ConstMap<Node, int> Excess; |
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175 | Excess excess(0); |
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176 | typedef ConstMap<Edge, int> LCap; |
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177 | LCap lcap(0); |
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178 | |
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179 | MinCostGenFlow<Graph, int, Excess, LCap> |
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180 | min_cost(g, excess, lcap, cap, flow, cost); |
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181 | min_cost.feasible(); |
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182 | min_cost.run(); |
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183 | |
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184 | std::cout << "elapsed time: " << ts << std::endl; |
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185 | std::cout << "flow value: "<< flow[e] << std::endl; |
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186 | } |
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