[388] | 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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