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 | |
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15 | using namespace lemon; |
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16 | |
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17 | // Use a DIMACS max flow file as stdin. |
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18 | // max_flow_demo < dimacs_max_flow_file |
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19 | |
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20 | template<typename Edge, typename EdgeIndexMap> |
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21 | class PrimalMap { |
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22 | protected: |
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23 | LPSolverWrapper* lp; |
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24 | EdgeIndexMap* edge_index_map; |
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25 | public: |
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26 | PrimalMap(LPSolverWrapper& _lp, EdgeIndexMap& _edge_index_map) : |
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27 | lp(&_lp), edge_index_map(&_edge_index_map) { } |
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28 | double operator[](Edge e) const { |
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29 | return lp->getPrimal((*edge_index_map)[e]); |
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30 | } |
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31 | }; |
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32 | |
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33 | int main(int, char **) { |
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34 | |
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35 | typedef ListGraph MutableGraph; |
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36 | typedef SmartGraph Graph; |
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37 | typedef Graph::Node Node; |
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38 | typedef Graph::EdgeIt EdgeIt; |
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39 | |
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40 | Graph g; |
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41 | |
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42 | Node s, t; |
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43 | Graph::EdgeMap<int> cap(g); |
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44 | //readDimacsMaxFlow(std::cin, g, s, t, cap); |
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45 | readDimacs(std::cin, g, cap, s, t); |
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46 | Timer ts; |
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47 | Graph::EdgeMap<int> flow(g); //0 flow |
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48 | Preflow<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> > |
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49 | max_flow_test(g, s, t, cap, flow); |
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50 | AugmentingFlow<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> > |
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51 | augmenting_flow_test(g, s, t, cap, flow); |
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52 | |
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53 | Graph::NodeMap<bool> cut(g); |
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54 | |
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55 | { |
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56 | std::cout << "preflow ..." << std::endl; |
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57 | ts.reset(); |
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58 | max_flow_test.run(); |
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59 | std::cout << "elapsed time: " << ts << std::endl; |
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60 | std::cout << "flow value: "<< max_flow_test.flowValue() << std::endl; |
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61 | max_flow_test.minCut(cut); |
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62 | |
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63 | for (Graph::EdgeIt e(g); e!=INVALID; ++e) { |
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64 | if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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65 | std::cout << "Slackness does not hold!" << std::endl; |
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66 | if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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67 | std::cout << "Slackness does not hold!" << std::endl; |
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68 | } |
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69 | } |
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70 | |
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71 | // { |
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72 | // std::cout << "preflow ..." << std::endl; |
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73 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0); |
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74 | // ts.reset(); |
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75 | // max_flow_test.preflow(Preflow<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> >::GEN_FLOW); |
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76 | // std::cout << "elapsed time: " << ts << std::endl; |
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77 | // std::cout << "flow value: "<< max_flow_test.flowValue() << std::endl; |
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78 | |
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79 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) { |
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80 | // if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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81 | // std::cout << "Slackness does not hold!" << std::endl; |
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82 | // if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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83 | // std::cout << "Slackness does not hold!" << std::endl; |
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84 | // } |
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85 | // } |
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86 | |
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87 | // { |
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88 | // std::cout << "wrapped preflow ..." << std::endl; |
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89 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0); |
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90 | // ts.reset(); |
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91 | // pre_flow_res.run(); |
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92 | // std::cout << "elapsed time: " << ts << std::endl; |
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93 | // std::cout << "flow value: "<< pre_flow_test.flowValue() << std::endl; |
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94 | // } |
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95 | |
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96 | { |
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97 | std::cout << "physical blocking flow augmentation ..." << std::endl; |
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98 | for (Graph::EdgeIt e(g); e!=INVALID; ++e) flow.set(e, 0); |
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99 | ts.reset(); |
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100 | int i=0; |
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101 | while (augmenting_flow_test.augmentOnBlockingFlow<MutableGraph>()) { ++i; } |
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102 | std::cout << "elapsed time: " << ts << std::endl; |
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103 | std::cout << "number of augmentation phases: " << i << std::endl; |
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104 | std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl; |
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105 | |
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106 | for (Graph::EdgeIt e(g); e!=INVALID; ++e) { |
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107 | if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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108 | std::cout << "Slackness does not hold!" << std::endl; |
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109 | if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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110 | std::cout << "Slackness does not hold!" << std::endl; |
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111 | } |
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112 | } |
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113 | |
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114 | // { |
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115 | // std::cout << "faster physical blocking flow augmentation ..." << std::endl; |
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116 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) 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 (max_flow_test.augmentOnBlockingFlow1<MutableGraph>()) { ++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: "<< max_flow_test.flowValue() << std::endl; |
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123 | // } |
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124 | |
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125 | { |
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126 | std::cout << "on-the-fly blocking flow augmentation ..." << std::endl; |
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127 | for (Graph::EdgeIt e(g); e!=INVALID; ++e) flow.set(e, 0); |
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128 | ts.reset(); |
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129 | int i=0; |
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130 | while (augmenting_flow_test.augmentOnBlockingFlow2()) { ++i; } |
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131 | std::cout << "elapsed time: " << ts << std::endl; |
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132 | std::cout << "number of augmentation phases: " << i << std::endl; |
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133 | std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl; |
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134 | |
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135 | for (Graph::EdgeIt e(g); e!=INVALID; ++e) { |
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136 | if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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137 | std::cout << "Slackness does not hold!" << std::endl; |
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138 | if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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139 | std::cout << "Slackness does not hold!" << std::endl; |
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140 | } |
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141 | } |
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142 | |
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143 | // { |
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144 | // std::cout << "on-the-fly shortest path augmentation ..." << std::endl; |
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145 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0); |
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146 | // ts.reset(); |
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147 | // int i=0; |
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148 | // while (augmenting_flow_test.augmentOnShortestPath()) { ++i; } |
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149 | // std::cout << "elapsed time: " << ts << std::endl; |
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150 | // std::cout << "number of augmentation phases: " << i << std::endl; |
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151 | // std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl; |
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152 | |
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153 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) { |
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154 | // if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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155 | // std::cout << "Slackness does not hold!" << std::endl; |
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156 | // if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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157 | // std::cout << "Slackness does not hold!" << std::endl; |
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158 | // } |
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159 | // } |
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160 | |
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161 | // { |
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162 | // std::cout << "on-the-fly shortest path augmentation ..." << std::endl; |
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163 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0); |
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164 | // ts.reset(); |
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165 | // int i=0; |
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166 | // while (augmenting_flow_test.augmentOnShortestPath2()) { ++i; } |
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167 | // std::cout << "elapsed time: " << ts << std::endl; |
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168 | // std::cout << "number of augmentation phases: " << i << std::endl; |
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169 | // std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl; |
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170 | |
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171 | // FOR_EACH_LOC(Graph::EdgeIt, e, g) { |
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172 | // if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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173 | // std::cout << "Slackness does not hold!" << std::endl; |
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174 | // if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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175 | // std::cout << "Slackness does not hold!" << std::endl; |
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176 | // } |
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177 | // } |
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178 | |
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179 | ts.reset(); |
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180 | LPSolverWrapper lp; |
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181 | lp.setMaximize(); |
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182 | typedef LPSolverWrapper::ColIt ColIt; |
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183 | typedef LPSolverWrapper::RowIt RowIt; |
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184 | typedef Graph::EdgeMap<ColIt> EdgeIndexMap; |
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185 | EdgeIndexMap edge_index_map(g); |
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186 | PrimalMap<Graph::Edge, EdgeIndexMap> lp_flow(lp, edge_index_map); |
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187 | for (Graph::EdgeIt e(g); e!=INVALID; ++e) { |
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188 | ColIt col_it=lp.addCol(); |
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189 | edge_index_map.set(e, col_it); |
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190 | lp.setColBounds(col_it, LPX_DB, 0.0, cap[e]); |
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191 | } |
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192 | for (Graph::NodeIt n(g); n!=INVALID; ++n) { |
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193 | if (n!=s) { |
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194 | //hurokelek miatt |
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195 | Graph::EdgeMap<int> coeffs(g, 0); |
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196 | for (Graph::InEdgeIt e(g, n); e!=INVALID; ++e) |
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197 | coeffs.set(e, coeffs[e]+1); |
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198 | for (Graph::OutEdgeIt e(g, n); e!=INVALID; ++e) |
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199 | coeffs.set(e, coeffs[e]-1); |
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200 | if (n==t) { |
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201 | for (Graph::EdgeIt e(g); e!=INVALID; ++e) { |
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202 | if (coeffs[e]!=0) |
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203 | lp.setObjCoef(edge_index_map[e], coeffs[e]); |
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204 | } |
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205 | } else { |
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206 | RowIt row_it=lp.addRow(); |
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207 | std::vector< std::pair<ColIt, double> > row; |
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208 | for (Graph::EdgeIt e(g); e!=INVALID; ++e) { |
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209 | if (coeffs[e]!=0) |
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210 | row.push_back(std::make_pair(edge_index_map[e], coeffs[e])); |
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211 | } |
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212 | lp.setRowCoeffs(row_it, row.begin(), row.end()); |
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213 | lp.setRowBounds(row_it, LPX_FX, 0.0, 0.0); |
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214 | } |
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215 | } |
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216 | } |
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217 | lp.solveSimplex(); |
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218 | std::cout << "flow value: "<< lp.getObjVal() << std::endl; |
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219 | std::cout << "elapsed time: " << ts << std::endl; |
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220 | |
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221 | return 0; |
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222 | } |
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