1 // -*- c++ -*- |
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2 |
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3 // Use a DIMACS max flow file as stdin. |
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4 // max_flow_demo < dimacs_max_flow_file |
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5 |
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6 #include <iostream> |
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7 #include <fstream> |
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8 |
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9 #include <lemon/smart_graph.h> |
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10 #include <lemon/list_graph.h> |
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11 #include <lemon/dimacs.h> |
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12 #include <lemon/time_measure.h> |
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13 #include <lemon/preflow.h> |
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14 #include <augmenting_flow.h> |
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15 #include <graph_concept.h> |
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16 |
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17 using namespace lemon; |
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18 |
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19 int main(int, char **) { |
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20 |
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21 typedef ListGraph MutableGraph; |
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22 typedef SmartGraph Graph; |
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23 typedef Graph::Node Node; |
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24 typedef Graph::EdgeIt EdgeIt; |
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25 |
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26 Graph g; |
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27 |
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28 Node s, t; |
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29 Graph::EdgeMap<int> cap(g); |
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30 //readDimacsMaxFlow(std::cin, g, s, t, cap); |
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31 readDimacs(std::cin, g, cap, s, t); |
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32 Timer ts; |
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33 Graph::EdgeMap<int> flow(g); //0 flow |
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34 Preflow<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> > |
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35 max_flow_test(g, s, t, cap, flow); |
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36 AugmentingFlow<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> > |
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37 augmenting_flow_test(g, s, t, cap, flow); |
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38 |
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39 Graph::NodeMap<bool> cut(g); |
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40 |
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41 { |
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42 std::cout << "preflow ..." << std::endl; |
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43 ts.reset(); |
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44 max_flow_test.run(); |
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45 std::cout << "elapsed time: " << ts << std::endl; |
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46 std::cout << "flow value: "<< max_flow_test.flowValue() << std::endl; |
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47 max_flow_test.minCut(cut); |
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48 |
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49 for(Graph::EdgeIt e(g); e!=INVALID; ++e) { |
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50 if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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51 std::cout << "Slackness does not hold!" << std::endl; |
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52 if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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53 std::cout << "Slackness does not hold!" << std::endl; |
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54 } |
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55 } |
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56 |
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57 { |
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58 std::cout << "preflow ..." << std::endl; |
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59 for(Graph::EdgeIt e(g); e!=INVALID; ++e) flow.set(e, 0); |
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60 ts.reset(); |
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61 max_flow_test.run(Preflow<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> >::GEN_FLOW); |
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62 std::cout << "elapsed time: " << ts << std::endl; |
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63 std::cout << "flow value: "<< max_flow_test.flowValue() << std::endl; |
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64 |
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65 for(Graph::EdgeIt e(g); e!=INVALID; ++e) { |
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66 if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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67 std::cout << "Slackness does not hold!" << std::endl; |
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68 if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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69 std::cout << "Slackness does not hold!" << std::endl; |
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70 } |
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71 } |
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72 |
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73 // { |
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74 // std::cout << "wrapped preflow ..." << std::endl; |
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75 // FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0); |
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76 // ts.reset(); |
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77 // pre_flow_res.run(); |
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78 // std::cout << "elapsed time: " << ts << std::endl; |
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79 // std::cout << "flow value: "<< pre_flow_test.flowValue() << std::endl; |
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80 // } |
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81 |
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82 { |
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83 std::cout << "physical blocking flow augmentation ..." << std::endl; |
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84 for(Graph::EdgeIt e(g); e!=INVALID; ++e) flow.set(e, 0); |
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85 ts.reset(); |
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86 int i=0; |
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87 while (augmenting_flow_test.augmentOnBlockingFlow<MutableGraph>()) { ++i; } |
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88 std::cout << "elapsed time: " << ts << std::endl; |
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89 std::cout << "number of augmentation phases: " << i << std::endl; |
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90 std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl; |
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91 |
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92 for(Graph::EdgeIt e(g); e!=INVALID; ++e) { |
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93 if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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94 std::cout << "Slackness does not hold!" << std::endl; |
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95 if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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96 std::cout << "Slackness does not hold!" << std::endl; |
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97 } |
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98 } |
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99 |
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100 { |
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101 std::cout << "on-the-fly blocking flow augmentation ..." << std::endl; |
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102 for(Graph::EdgeIt e(g); e!=INVALID; ++e) flow.set(e, 0); |
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103 ts.reset(); |
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104 int i=0; |
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105 while (augmenting_flow_test.augmentOnBlockingFlow2()) { ++i; } |
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106 std::cout << "elapsed time: " << ts << std::endl; |
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107 std::cout << "number of augmentation phases: " << i << std::endl; |
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108 std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl; |
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109 |
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110 for(Graph::EdgeIt e(g); e!=INVALID; ++e) { |
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111 if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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112 std::cout << "Slackness does not hold!" << std::endl; |
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113 if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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114 std::cout << "Slackness does not hold!" << std::endl; |
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115 } |
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116 } |
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117 |
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118 { |
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119 std::cout << "on-the-fly shortest path augmentation ..." << std::endl; |
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120 for(Graph::EdgeIt e(g); e!=INVALID; ++e) flow.set(e, 0); |
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121 ts.reset(); |
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122 int i=0; |
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123 while (augmenting_flow_test.augmentOnShortestPath()) { ++i; } |
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124 std::cout << "elapsed time: " << ts << std::endl; |
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125 std::cout << "number of augmentation phases: " << i << std::endl; |
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126 std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl; |
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127 |
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128 for(Graph::EdgeIt e(g); e!=INVALID; ++e) { |
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129 if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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130 std::cout << "Slackness does not hold!" << std::endl; |
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131 if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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132 std::cout << "Slackness does not hold!" << std::endl; |
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133 } |
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134 } |
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135 |
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136 { |
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137 std::cout << "on-the-fly shortest path augmentation ..." << std::endl; |
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138 for(Graph::EdgeIt e(g); e!=INVALID; ++e) flow.set(e, 0); |
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139 ts.reset(); |
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140 int i=0; |
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141 while (augmenting_flow_test.augmentOnShortestPath2()) { ++i; } |
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142 std::cout << "elapsed time: " << ts << std::endl; |
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143 std::cout << "number of augmentation phases: " << i << std::endl; |
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144 std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl; |
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145 |
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146 for(Graph::EdgeIt e(g); e!=INVALID; ++e) { |
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147 if (cut[g.source(e)] && !cut[g.target(e)] && !flow[e]==cap[e]) |
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148 std::cout << "Slackness does not hold!" << std::endl; |
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149 if (!cut[g.source(e)] && cut[g.target(e)] && flow[e]>0) |
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150 std::cout << "Slackness does not hold!" << std::endl; |
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151 } |
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152 } |
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153 |
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154 return 0; |
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155 } |
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