src/work/jacint/max_flow_test.cc
changeset 1365 c280de819a73
parent 921 818510fa3d99
equal deleted inserted replaced
4:a8bc0595338a -1:000000000000
     1 #include <iostream>
       
     2 
       
     3 #include <lemon/list_graph.h>
       
     4 #include <lemon/dimacs.h>
       
     5 #include <max_flow.h>
       
     6 #include <max_flow_no_stack.h>
       
     7 #include <lemon/time_measure.h>
       
     8 
       
     9 using namespace lemon;
       
    10 
       
    11 int main(int, char **) {
       
    12  
       
    13   typedef ListGraph Graph;
       
    14   
       
    15   typedef Graph::Node Node;
       
    16   typedef Graph::EdgeIt EdgeIt;
       
    17 
       
    18   Graph G;
       
    19   Node s, t;
       
    20   Graph::EdgeMap<int> cap(G);
       
    21   readDimacs(std::cin, G, cap, s, t);
       
    22   Timer ts;
       
    23   
       
    24   std::cout <<
       
    25     "\n  Running max_flow.h on a graph with " << 
       
    26     G.nodeNum() << " nodes and " << G.edgeNum() << " edges..."
       
    27 	   << std::endl<<std::endl;
       
    28 
       
    29   Graph::EdgeMap<int> flowstack(G,0);
       
    30   MaxFlow<Graph, int> max_flow_test(G, s, t, cap, flowstack);
       
    31   ts.reset();
       
    32   max_flow_test.run();
       
    33   std::cout << "Elapsed time of run() with stl stack: " << std::endl 
       
    34 	    <<ts << std::endl;
       
    35 
       
    36   Graph::EdgeMap<int> flow(G,0);
       
    37   MaxFlowNoStack<Graph, int> max_flow_test_no_stack(G, s, t, cap, flow);
       
    38   ts.reset();
       
    39   max_flow_test_no_stack.run();
       
    40   std::cout << "Elapsed time of run() without stack: " << std::endl 
       
    41 	    <<ts << std::endl;
       
    42   
       
    43   Graph::NodeMap<bool> mincut(G);
       
    44   max_flow_test_no_stack.minMinCut(mincut); 
       
    45   int min_min_cut_value=0;
       
    46   EdgeIt e;
       
    47   for(G.first(e); G.valid(e); G.next(e)) {
       
    48     if (mincut[G.source(e)] && !mincut[G.target(e)]) min_min_cut_value+=cap[e];
       
    49   }
       
    50 
       
    51   Graph::NodeMap<bool> cut(G);
       
    52   max_flow_test_no_stack.minCut(cut); 
       
    53   int min_cut_value=0;
       
    54   for(G.first(e); G.valid(e); G.next(e)) {
       
    55     if (cut[G.source(e)] && !cut[G.target(e)]) 
       
    56       min_cut_value+=cap[e];
       
    57   }
       
    58 
       
    59   Graph::NodeMap<bool> maxcut(G);
       
    60   max_flow_test_no_stack.maxMinCut(maxcut); 
       
    61   int max_min_cut_value=0;
       
    62   for(G.first(e); G.valid(e); G.next(e)) {
       
    63     if (maxcut[G.source(e)] && !maxcut[G.target(e)]) 
       
    64       max_min_cut_value+=cap[e];
       
    65       }
       
    66 
       
    67   std::cout << "\n Checking the result without stack: " <<std::endl;  
       
    68   std::cout << "Flow value: "<< max_flow_test_no_stack.flowValue() << std::endl;
       
    69   std::cout << "Min cut value: "<< min_cut_value << std::endl;
       
    70   std::cout << "Min min cut value: "<< min_min_cut_value << std::endl;
       
    71   std::cout << "Max min cut value: "<< max_min_cut_value << 
       
    72     std::endl;
       
    73 
       
    74   if ( max_flow_test_no_stack.flowValue() == min_cut_value &&
       
    75        min_cut_value == min_min_cut_value &&
       
    76        min_min_cut_value == max_min_cut_value )
       
    77     std::cout << "They are equal! " <<std::endl<< std::endl<<"\n";  
       
    78 
       
    79   /*
       
    80 
       
    81   Graph::EdgeMap<int> flow2(G,0);
       
    82   std::cout << "Calling resetFlow() " << std::endl 
       
    83 	    << ts << std::endl;
       
    84   max_flow_test.setFlow(flow2);  
       
    85   ts.reset();
       
    86   max_flow_test.preflow(max_flow_test.PRE_FLOW);
       
    87   std::cout << "Elapsed time of preflow(PRE_FLOW) starting from the zero flow: " << std::endl 
       
    88 	    << ts << std::endl;
       
    89   
       
    90   Graph::NodeMap<bool> mincut2(G);
       
    91   max_flow_test.minMinCut(mincut2); 
       
    92   int min_min_cut_value2=0;
       
    93     for(G.first(e); G.valid(e); G.next(e)) {
       
    94     if (mincut2[G.source(e)] && !mincut2[G.target(e)]) min_min_cut_value2+=cap[e];
       
    95   }
       
    96 
       
    97   Graph::NodeMap<bool> cut2(G);
       
    98   max_flow_test.minCut(cut2); 
       
    99   int min_cut_value2=0;
       
   100   for(G.first(e); G.valid(e); G.next(e)) {
       
   101     if (cut2[G.source(e)] && !cut2[G.target(e)]) 
       
   102       min_cut_value2+=cap[e];
       
   103   }
       
   104 
       
   105   Graph::NodeMap<bool> maxcut2(G);
       
   106   max_flow_test.maxMinCut(maxcut2); 
       
   107   int max_min_cut_value2=0;
       
   108   for(G.first(e); G.valid(e); G.next(e)) {
       
   109     if (maxcut2[G.source(e)] && !maxcut2[G.target(e)]) 
       
   110       max_min_cut_value2+=cap[e];
       
   111       }
       
   112   
       
   113   std::cout << "\n Checking the result: " <<std::endl;  
       
   114   std::cout << "Flow value: "<< max_flow_test.flowValue() << std::endl;
       
   115   std::cout << "Min cut value: "<< min_cut_value2 << std::endl;
       
   116   std::cout << "Min min cut value: "<< min_min_cut_value2 << std::endl;
       
   117   std::cout << "Max min cut value: "<< max_min_cut_value2 << 
       
   118     std::endl;  
       
   119   if ( max_flow_test.flowValue() == min_cut_value &&
       
   120        min_cut_value == min_min_cut_value &&
       
   121        min_min_cut_value == max_min_cut_value )
       
   122     std::cout << "They are equal! " <<std::endl;  
       
   123 
       
   124 
       
   125   MaxFlow<Graph, int> max_flow_test3(G, s, t, cap, flow2);
       
   126   max_flow_test3.run(max_flow_test3.GEN_FLOW);
       
   127   std::cout << "Calling run(GEN_FLOW) from the max flow found before. " <<std::endl;  
       
   128   
       
   129   Graph::NodeMap<bool> mincut3(G);
       
   130   max_flow_test3.minMinCut(mincut3); 
       
   131   int min_min_cut_value3=0;
       
   132   for(G.first(e); G.valid(e); G.next(e)) {
       
   133     if (mincut3[G.source(e)] && !mincut3[G.target(e)]) min_min_cut_value3+=cap[e];
       
   134   }
       
   135 
       
   136   Graph::NodeMap<bool> cut3(G);
       
   137   max_flow_test3.minCut(cut3); 
       
   138   int min_cut_value3=0;
       
   139   for(G.first(e); G.valid(e); G.next(e)) {
       
   140     if (cut3[G.source(e)] && !cut3[G.target(e)]) 
       
   141       min_cut_value3+=cap[e];
       
   142   }
       
   143 
       
   144   Graph::NodeMap<bool> maxcut3(G);
       
   145   max_flow_test3.maxMinCut(maxcut3); 
       
   146   int max_min_cut_value3=0;
       
   147   for(G.first(e); G.valid(e); G.next(e)) {
       
   148     if (maxcut3[G.source(e)] && !maxcut3[G.target(e)]) 
       
   149       max_min_cut_value3+=cap[e];
       
   150   }
       
   151 
       
   152   std::cout << "\n Checking the result: " <<std::endl;  
       
   153   std::cout << "Flow value: "<< max_flow_test3.flowValue() << std::endl;
       
   154   std::cout << "Min cut value: "<< min_cut_value3 << std::endl;
       
   155   std::cout << "Min min cut value: "<< min_min_cut_value3 << std::endl;
       
   156   std::cout << "Max min cut value: "<< max_min_cut_value3 << 
       
   157     std::endl;
       
   158 
       
   159   if ( max_flow_test3.flowValue() == min_cut_value3 &&
       
   160        min_cut_value3 == min_min_cut_value3 &&
       
   161        min_min_cut_value3 == max_min_cut_value3 )
       
   162     std::cout << "They are equal! " <<std::endl<< std::endl<<"\n";  
       
   163   */
       
   164   
       
   165   return 0;
       
   166 }