src/work/jacint/max_flow_test.cc
author athos
Tue, 11 May 2004 16:38:17 +0000
changeset 611 83530dad618a
child 715 665689d86225
permissions -rw-r--r--
Some modifications and another testfile.
     1 #include <iostream>
     2 
     3 #include <list_graph.h>
     4 #include <dimacs.h>
     5 #include <max_flow.h>
     6 #include <time_measure.h>
     7 
     8 using namespace hugo;
     9 
    10 int main(int, char **) {
    11  
    12   typedef ListGraph Graph;
    13   
    14   typedef Graph::Node Node;
    15   typedef Graph::EdgeIt EdgeIt;
    16 
    17   Graph G;
    18   Node s, t;
    19   Graph::EdgeMap<int> cap(G);
    20   readDimacs(std::cin, G, cap, s, t);
    21   Timer ts;
    22   
    23   std::cout <<
    24     "\n  Running max_flow.h on a graph with " << 
    25     G.nodeNum() << " nodes and " << G.edgeNum() << " edges..."
    26 	   << std::endl<<std::endl;
    27 
    28   Graph::EdgeMap<int> flow(G,0);
    29   MaxFlow<Graph, int> max_flow_test(G, s, t, cap, flow);
    30   ts.reset();
    31   max_flow_test.run();
    32   std::cout << "Elapsed time of run(): " << std::endl 
    33 	    <<ts << std::endl;
    34   
    35   Graph::NodeMap<bool> mincut(G);
    36   max_flow_test.minMinCut(mincut); 
    37   int min_min_cut_value=0;
    38   EdgeIt e;
    39   for(G.first(e); G.valid(e); G.next(e)) {
    40     if (mincut[G.tail(e)] && !mincut[G.head(e)]) min_min_cut_value+=cap[e];
    41   }
    42 
    43   Graph::NodeMap<bool> cut(G);
    44   max_flow_test.minCut(cut); 
    45   int min_cut_value=0;
    46   for(G.first(e); G.valid(e); G.next(e)) {
    47     if (cut[G.tail(e)] && !cut[G.head(e)]) 
    48       min_cut_value+=cap[e];
    49   }
    50 
    51   Graph::NodeMap<bool> maxcut(G);
    52   max_flow_test.maxMinCut(maxcut); 
    53   int max_min_cut_value=0;
    54   for(G.first(e); G.valid(e); G.next(e)) {
    55     if (maxcut[G.tail(e)] && !maxcut[G.head(e)]) 
    56       max_min_cut_value+=cap[e];
    57       }
    58 
    59   std::cout << "\n Checking the result: " <<std::endl;  
    60   std::cout << "Flow value: "<< max_flow_test.flowValue() << std::endl;
    61   std::cout << "Min cut value: "<< min_cut_value << std::endl;
    62   std::cout << "Min min cut value: "<< min_min_cut_value << std::endl;
    63   std::cout << "Max min cut value: "<< max_min_cut_value << 
    64     std::endl;
    65 
    66   if ( max_flow_test.flowValue() == min_cut_value &&
    67        min_cut_value == min_min_cut_value &&
    68        min_min_cut_value == max_min_cut_value )
    69     std::cout << "They are equal! " <<std::endl<< std::endl<<"\n";  
    70 
    71 
    72 
    73   Graph::EdgeMap<int> flow2(G,0);
    74   std::cout << "Calling resetFlow() " << std::endl 
    75 	    << ts << std::endl;
    76   max_flow_test.resetFlow(flow2);  
    77   ts.reset();
    78   max_flow_test.preflow(max_flow_test.PRE_FLOW);
    79   std::cout << "Elapsed time of preflow(PRE_FLOW) starting from the zero flow: " << std::endl 
    80 	    << ts << std::endl;
    81   
    82   Graph::NodeMap<bool> mincut2(G);
    83   max_flow_test.minMinCut(mincut2); 
    84   int min_min_cut_value2=0;
    85     for(G.first(e); G.valid(e); G.next(e)) {
    86     if (mincut2[G.tail(e)] && !mincut2[G.head(e)]) min_min_cut_value2+=cap[e];
    87   }
    88 
    89   Graph::NodeMap<bool> cut2(G);
    90   max_flow_test.minCut(cut2); 
    91   int min_cut_value2=0;
    92   for(G.first(e); G.valid(e); G.next(e)) {
    93     if (cut2[G.tail(e)] && !cut2[G.head(e)]) 
    94       min_cut_value2+=cap[e];
    95   }
    96 
    97   Graph::NodeMap<bool> maxcut2(G);
    98   max_flow_test.maxMinCut(maxcut2); 
    99   int max_min_cut_value2=0;
   100   for(G.first(e); G.valid(e); G.next(e)) {
   101     if (maxcut2[G.tail(e)] && !maxcut2[G.head(e)]) 
   102       max_min_cut_value2+=cap[e];
   103       }
   104   
   105   std::cout << "\n Checking the result: " <<std::endl;  
   106   std::cout << "Flow value: "<< max_flow_test.flowValue() << std::endl;
   107   std::cout << "Min cut value: "<< min_cut_value2 << std::endl;
   108   std::cout << "Min min cut value: "<< min_min_cut_value2 << std::endl;
   109   std::cout << "Max min cut value: "<< max_min_cut_value2 << 
   110     std::endl;  
   111   if ( max_flow_test.flowValue() == min_cut_value &&
   112        min_cut_value == min_min_cut_value &&
   113        min_min_cut_value == max_min_cut_value )
   114     std::cout << "They are equal! " <<std::endl;  
   115 
   116 
   117   MaxFlow<Graph, int> max_flow_test3(G, s, t, cap, flow2);
   118   max_flow_test3.run(max_flow_test3.GEN_FLOW);
   119   std::cout << "Calling run(GEN_FLOW) from the max flow found before. " <<std::endl;  
   120   
   121   Graph::NodeMap<bool> mincut3(G);
   122   max_flow_test3.minMinCut(mincut3); 
   123   int min_min_cut_value3=0;
   124   for(G.first(e); G.valid(e); G.next(e)) {
   125     if (mincut3[G.tail(e)] && !mincut3[G.head(e)]) min_min_cut_value3+=cap[e];
   126   }
   127 
   128   Graph::NodeMap<bool> cut3(G);
   129   max_flow_test3.minCut(cut3); 
   130   int min_cut_value3=0;
   131   for(G.first(e); G.valid(e); G.next(e)) {
   132     if (cut3[G.tail(e)] && !cut3[G.head(e)]) 
   133       min_cut_value3+=cap[e];
   134   }
   135 
   136   Graph::NodeMap<bool> maxcut3(G);
   137   max_flow_test3.maxMinCut(maxcut3); 
   138   int max_min_cut_value3=0;
   139   for(G.first(e); G.valid(e); G.next(e)) {
   140     if (maxcut3[G.tail(e)] && !maxcut3[G.head(e)]) 
   141       max_min_cut_value3+=cap[e];
   142   }
   143 
   144   std::cout << "\n Checking the result: " <<std::endl;  
   145   std::cout << "Flow value: "<< max_flow_test3.flowValue() << std::endl;
   146   std::cout << "Min cut value: "<< min_cut_value3 << std::endl;
   147   std::cout << "Min min cut value: "<< min_min_cut_value3 << std::endl;
   148   std::cout << "Max min cut value: "<< max_min_cut_value3 << 
   149     std::endl;
   150 
   151   if ( max_flow_test3.flowValue() == min_cut_value3 &&
   152        min_cut_value3 == min_min_cut_value3 &&
   153        min_min_cut_value3 == max_min_cut_value3 )
   154     std::cout << "They are equal! " <<std::endl<< std::endl<<"\n";  
   155   
   156   return 0;
   157 }