src/work/jacint/max_flow_test.cc
author alpar
Thu, 31 Mar 2005 13:30:27 +0000
changeset 1282 81e89e2b90d1
parent 921 818510fa3d99
permissions -rw-r--r--
length() returns int istead of size_t
     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 }