src/work/jacint/max_flow_bug.cc
author alpar
Thu, 05 Aug 2004 08:53:09 +0000
changeset 757 8680351d0c28
parent 748 a0e497db23ee
child 921 818510fa3d99
permissions -rw-r--r--
resetXxx() changed to setXxx().
     1 #include <iostream>
     2 
     3 //#include <hugo/list_graph.h>
     4 #include <sage_graph.h>
     5 #include <hugo/dimacs.h>
     6 #include <hugo/max_flow.h>
     7 //#include <max_flow_no_stack.h>
     8 #include <hugo/time_measure.h>
     9 
    10 using namespace hugo;
    11 
    12 int main(int, char **) {
    13  
    14 //  typedef ListGraph Graph;
    15   typedef SageGraph Graph;
    16   
    17   typedef Graph::Node Node;
    18   typedef Graph::EdgeIt EdgeIt;
    19 
    20   Graph G;
    21   Node s, t;
    22   Graph::EdgeMap<int> cap(G);
    23   Graph::EdgeMap<int> flow(G,0);
    24 
    25   readDimacs(std::cin, G, cap, s, t, flow);
    26   Timer ts;
    27   
    28   std::cout <<
    29     "\n  Running max_flow.h on a graph with " << 
    30     G.nodeNum() << " nodes and " << G.edgeNum() << " edges..."
    31 	   << std::endl<<std::endl;
    32 
    33 
    34   MaxFlow<Graph, int> max_flow_test_no_stack(G, s, t, cap, flow);
    35   ts.reset();
    36   max_flow_test_no_stack.preflowPhase1(MaxFlow<Graph, int>::PRE_FLOW);
    37   std::cout << "Elapsed time of run() without stack: " << std::endl 
    38 	    <<ts << std::endl;
    39   
    40   Graph::NodeMap<bool> mincut(G);
    41   max_flow_test_no_stack.minMinCut(mincut); 
    42   int min_min_cut_value=0;
    43   EdgeIt e;
    44   for(G.first(e); G.valid(e); G.next(e)) {
    45     if (mincut[G.tail(e)] && !mincut[G.head(e)]) min_min_cut_value+=cap[e];
    46   }
    47 
    48   Graph::NodeMap<bool> cut(G);
    49   max_flow_test_no_stack.minCut(cut); 
    50   int min_cut_value=0;
    51   for(G.first(e); G.valid(e); G.next(e)) {
    52     if (cut[G.tail(e)] && !cut[G.head(e)]) 
    53       min_cut_value+=cap[e];
    54   }
    55 
    56   Graph::NodeMap<bool> maxcut(G);
    57   max_flow_test_no_stack.maxMinCut(maxcut); 
    58   int max_min_cut_value=0;
    59   for(G.first(e); G.valid(e); G.next(e)) {
    60     if (maxcut[G.tail(e)] && !maxcut[G.head(e)]) 
    61       max_min_cut_value+=cap[e];
    62       }
    63 
    64   std::cout << "\n Checking the result without stack: " <<std::endl;  
    65   std::cout << "Flow value: "<< max_flow_test_no_stack.flowValue() << std::endl;
    66   std::cout << "Min cut value: "<< min_cut_value << std::endl;
    67   std::cout << "Min min cut value: "<< min_min_cut_value << std::endl;
    68   std::cout << "Max min cut value: "<< max_min_cut_value << 
    69     std::endl;
    70 
    71   if ( max_flow_test_no_stack.flowValue() == min_cut_value &&
    72        min_cut_value == min_min_cut_value &&
    73        min_min_cut_value == max_min_cut_value )
    74     std::cout << "They are equal! " <<std::endl<< std::endl<<"\n";  
    75 
    76   /*
    77 
    78   Graph::EdgeMap<int> flow2(G,0);
    79   std::cout << "Calling setFlow() " << std::endl 
    80 	    << ts << std::endl;
    81   max_flow_test.setFlow(flow2);  
    82   ts.reset();
    83   max_flow_test.preflow(max_flow_test.PRE_FLOW);
    84   std::cout << "Elapsed time of preflow(PRE_FLOW) starting from the zero flow: " << std::endl 
    85 	    << ts << std::endl;
    86   
    87   Graph::NodeMap<bool> mincut2(G);
    88   max_flow_test.minMinCut(mincut2); 
    89   int min_min_cut_value2=0;
    90     for(G.first(e); G.valid(e); G.next(e)) {
    91     if (mincut2[G.tail(e)] && !mincut2[G.head(e)]) min_min_cut_value2+=cap[e];
    92   }
    93 
    94   Graph::NodeMap<bool> cut2(G);
    95   max_flow_test.minCut(cut2); 
    96   int min_cut_value2=0;
    97   for(G.first(e); G.valid(e); G.next(e)) {
    98     if (cut2[G.tail(e)] && !cut2[G.head(e)]) 
    99       min_cut_value2+=cap[e];
   100   }
   101 
   102   Graph::NodeMap<bool> maxcut2(G);
   103   max_flow_test.maxMinCut(maxcut2); 
   104   int max_min_cut_value2=0;
   105   for(G.first(e); G.valid(e); G.next(e)) {
   106     if (maxcut2[G.tail(e)] && !maxcut2[G.head(e)]) 
   107       max_min_cut_value2+=cap[e];
   108       }
   109   
   110   std::cout << "\n Checking the result: " <<std::endl;  
   111   std::cout << "Flow value: "<< max_flow_test.flowValue() << std::endl;
   112   std::cout << "Min cut value: "<< min_cut_value2 << std::endl;
   113   std::cout << "Min min cut value: "<< min_min_cut_value2 << std::endl;
   114   std::cout << "Max min cut value: "<< max_min_cut_value2 << 
   115     std::endl;  
   116   if ( max_flow_test.flowValue() == min_cut_value &&
   117        min_cut_value == min_min_cut_value &&
   118        min_min_cut_value == max_min_cut_value )
   119     std::cout << "They are equal! " <<std::endl;  
   120 
   121 
   122   MaxFlow<Graph, int> max_flow_test3(G, s, t, cap, flow2);
   123   max_flow_test3.run(max_flow_test3.GEN_FLOW);
   124   std::cout << "Calling run(GEN_FLOW) from the max flow found before. " <<std::endl;  
   125   
   126   Graph::NodeMap<bool> mincut3(G);
   127   max_flow_test3.minMinCut(mincut3); 
   128   int min_min_cut_value3=0;
   129   for(G.first(e); G.valid(e); G.next(e)) {
   130     if (mincut3[G.tail(e)] && !mincut3[G.head(e)]) min_min_cut_value3+=cap[e];
   131   }
   132 
   133   Graph::NodeMap<bool> cut3(G);
   134   max_flow_test3.minCut(cut3); 
   135   int min_cut_value3=0;
   136   for(G.first(e); G.valid(e); G.next(e)) {
   137     if (cut3[G.tail(e)] && !cut3[G.head(e)]) 
   138       min_cut_value3+=cap[e];
   139   }
   140 
   141   Graph::NodeMap<bool> maxcut3(G);
   142   max_flow_test3.maxMinCut(maxcut3); 
   143   int max_min_cut_value3=0;
   144   for(G.first(e); G.valid(e); G.next(e)) {
   145     if (maxcut3[G.tail(e)] && !maxcut3[G.head(e)]) 
   146       max_min_cut_value3+=cap[e];
   147   }
   148 
   149   std::cout << "\n Checking the result: " <<std::endl;  
   150   std::cout << "Flow value: "<< max_flow_test3.flowValue() << std::endl;
   151   std::cout << "Min cut value: "<< min_cut_value3 << std::endl;
   152   std::cout << "Min min cut value: "<< min_min_cut_value3 << std::endl;
   153   std::cout << "Max min cut value: "<< max_min_cut_value3 << 
   154     std::endl;
   155 
   156   if ( max_flow_test3.flowValue() == min_cut_value3 &&
   157        min_cut_value3 == min_min_cut_value3 &&
   158        min_min_cut_value3 == max_min_cut_value3 )
   159     std::cout << "They are equal! " <<std::endl<< std::endl<<"\n";  
   160   */
   161   
   162   return 0;
   163 }