1 | /* |
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2 | The only difference between preflow.h and preflow_res.h is that the latter |
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3 | uses the ResGraphWrapper, while the first does not. (Bfs is implemented by |
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4 | hand in both.) This test program runs Preflow and PreflowRes on the same |
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5 | graph, tests the result of these implementations and writes the running time |
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6 | of them. */ |
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7 | #include <iostream> |
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8 | |
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9 | #include <smart_graph.h> |
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10 | #include <dimacs.h> |
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11 | #include <preflow.h> |
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12 | #include <preflow_res.h> |
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13 | #include <time_measure.h> |
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14 | |
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15 | using namespace hugo; |
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16 | |
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17 | int main(int, char **) { |
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18 | |
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19 | typedef SmartGraph Graph; |
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20 | |
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21 | typedef Graph::Node Node; |
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22 | typedef Graph::EdgeIt EdgeIt; |
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23 | |
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24 | Graph G; |
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25 | Node s, t; |
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26 | Graph::EdgeMap<int> cap(G); |
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27 | readDimacsMaxFlow(std::cin, G, s, t, cap); |
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28 | Timer ts; |
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29 | |
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30 | std::cout << |
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31 | "\n In which way are we faster: using ResGraphWrapper or not?" |
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32 | <<std::endl; |
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33 | std::cout << |
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34 | "\n Running preflow.h on a graph with " << |
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35 | G.nodeNum() << " nodes and " << G.edgeNum() << " edges..." |
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36 | << std::endl<<std::endl; |
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37 | |
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38 | |
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39 | |
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40 | Graph::EdgeMap<int> flow(G,0); |
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41 | Preflow<Graph, int> max_flow_test(G, s, t, cap, flow, 1); |
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42 | ts.reset(); |
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43 | max_flow_test.run(); |
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44 | std::cout << "Elapsed time NOT using the ResGraphWrapper: " << std::endl |
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45 | <<ts << std::endl; |
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46 | |
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47 | Graph::NodeMap<bool> mincut(G); |
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48 | max_flow_test.minMinCut(mincut); |
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49 | int min_min_cut_value=0; |
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50 | EdgeIt e; |
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51 | for(G.first(e); G.valid(e); G.next(e)) { |
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52 | if (mincut[G.tail(e)] && !mincut[G.head(e)]) min_min_cut_value+=cap[e]; |
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53 | } |
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54 | |
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55 | Graph::NodeMap<bool> cut(G); |
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56 | max_flow_test.minCut(cut); |
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57 | int min_cut_value=0; |
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58 | for(G.first(e); G.valid(e); G.next(e)) { |
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59 | if (cut[G.tail(e)] && !cut[G.head(e)]) |
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60 | min_cut_value+=cap[e]; |
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61 | } |
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62 | |
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63 | Graph::NodeMap<bool> maxcut(G); |
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64 | max_flow_test.maxMinCut(maxcut); |
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65 | int max_min_cut_value=0; |
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66 | for(G.first(e); G.valid(e); G.next(e)) { |
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67 | if (maxcut[G.tail(e)] && !maxcut[G.head(e)]) |
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68 | max_min_cut_value+=cap[e]; |
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69 | } |
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70 | |
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71 | std::cout << "\n Checking the result: " <<std::endl; |
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72 | std::cout << "Flow value: "<< max_flow_test.flowValue() << std::endl; |
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73 | std::cout << "Min cut value: "<< min_cut_value << std::endl; |
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74 | std::cout << "Min min cut value: "<< min_min_cut_value << std::endl; |
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75 | std::cout << "Max min cut value: "<< max_min_cut_value << |
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76 | std::endl; |
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77 | |
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78 | if ( max_flow_test.flowValue() == min_cut_value && |
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79 | min_cut_value == min_min_cut_value && |
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80 | min_min_cut_value == max_min_cut_value ) |
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81 | std::cout << "They are equal! " <<std::endl<< std::endl<<"\n"; |
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82 | |
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83 | Graph::EdgeMap<int> flow2(G,0); |
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84 | PreflowRes<Graph, int> max_flow_test2(G, s, t, cap, flow2, 1); |
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85 | ts.reset(); |
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86 | max_flow_test2.run(); |
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87 | std::cout << "Elapsed time using the ResGraphWrapper: " << std::endl |
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88 | << ts << std::endl; |
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89 | |
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90 | Graph::NodeMap<bool> mincut2(G); |
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91 | max_flow_test2.minMinCut(mincut2); |
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92 | int min_min_cut_value2=0; |
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93 | for(G.first(e); G.valid(e); G.next(e)) { |
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94 | if (mincut2[G.tail(e)] && !mincut2[G.head(e)]) min_min_cut_value2+=cap[e]; |
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95 | } |
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96 | |
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97 | Graph::NodeMap<bool> cut2(G); |
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98 | max_flow_test2.minCut(cut2); |
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99 | int min_cut_value2=0; |
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100 | for(G.first(e); G.valid(e); G.next(e)) { |
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101 | if (cut2[G.tail(e)] && !cut2[G.head(e)]) |
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102 | min_cut_value2+=cap[e]; |
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103 | } |
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104 | |
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105 | Graph::NodeMap<bool> maxcut2(G); |
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106 | max_flow_test2.maxMinCut(maxcut2); |
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107 | int max_min_cut_value2=0; |
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108 | for(G.first(e); G.valid(e); G.next(e)) { |
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109 | if (maxcut2[G.tail(e)] && !maxcut2[G.head(e)]) |
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110 | max_min_cut_value2+=cap[e]; |
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111 | } |
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112 | |
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113 | std::cout << "\n Checking the result: " <<std::endl; |
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114 | std::cout << "Flow value: "<< max_flow_test2.flowValue() << std::endl; |
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115 | std::cout << "Min cut value: "<< min_cut_value2 << std::endl; |
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116 | std::cout << "Min min cut value: "<< min_min_cut_value2 << std::endl; |
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117 | std::cout << "Max min cut value: "<< max_min_cut_value2 << |
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118 | std::endl; |
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119 | if ( max_flow_test.flowValue() == min_cut_value && |
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120 | min_cut_value == min_min_cut_value && |
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121 | min_min_cut_value == max_min_cut_value ) |
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122 | std::cout << "They are equal! " <<std::endl<<"/n"; |
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123 | |
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124 | return 0; |
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125 | } |
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