src/work/jacint/preflow_hl4.cc
author jacint
Sun, 22 Feb 2004 12:17:16 +0000
changeset 113 cf7b01232d86
permissions -rw-r--r--
*** empty log message ***
     1 #include <iostream>
     2 #include <fstream>
     3 
     4 #include <list_graph.hh>
     5 #include <dimacs.hh>
     6 #include <preflow_hl4.h>
     7 #include <time_measure.h>
     8 
     9 using namespace hugo;
    10 
    11 //Note, that preflow_hl4.h has a member NodeMap<bool> cut, 
    12 //the construction of which slowing the running time by 1-10%.
    13 
    14 // Use a DIMACS max flow file as stdin.
    15 // read_dimacs_demo < dimacs_max_flow_file
    16 int main(int, char **) {
    17   typedef ListGraph::NodeIt NodeIt;
    18   typedef ListGraph::EachEdgeIt EachEdgeIt;
    19 
    20   ListGraph G;
    21   NodeIt s, t;
    22   ListGraph::EdgeMap<int> cap(G);
    23   readDimacsMaxFlow(std::cin, G, s, t, cap);
    24 
    25   std::cout << "preflow_hl4 demo ..." << std::endl;
    26   
    27   double mintime=1000000;
    28 
    29   for ( int i=1; i!=11; ++i ) {
    30     double pre_time=currTime();
    31     preflow_hl4<ListGraph, int> max_flow_test(G, s, t, cap);
    32     double post_time=currTime();
    33     if ( mintime > post_time-pre_time ) mintime = post_time-pre_time;
    34   }
    35 
    36   double pre_time=currTime();
    37   preflow_hl4<ListGraph, int> max_flow_test(G, s, t, cap);
    38   double post_time=currTime();
    39      
    40   ListGraph::NodeMap<bool> cut(G);
    41   max_flow_test.minCut(cut); 
    42   int min_cut_value=0;
    43   for(EachEdgeIt e=G.first<EachEdgeIt>(); e.valid(); ++e) {
    44     if (cut.get(G.tail(e)) && !cut.get(G.head(e))) min_cut_value+=cap.get(e);
    45   }
    46 
    47   ListGraph::NodeMap<bool> cut1(G);
    48   max_flow_test.minMinCut(cut1); 
    49   int min_min_cut_value=0;
    50   for(EachEdgeIt e=G.first<EachEdgeIt>(); e.valid(); ++e) {
    51     if (cut.get(G.tail(e)) && !cut.get(G.head(e))) 
    52       min_min_cut_value+=cap.get(e);
    53   }
    54 
    55   ListGraph::NodeMap<bool> cut2(G);
    56   max_flow_test.maxMinCut(cut2); 
    57   int max_min_cut_value=0;
    58   for(EachEdgeIt e=G.first<EachEdgeIt>(); e.valid(); ++e) {
    59     if (cut2.get(G.tail(e)) && !cut2.get(G.head(e))) 
    60       max_min_cut_value+=cap.get(e);
    61   }
    62   
    63   std::cout << "min time of 10 runs: " << mintime << " sec"<< std::endl; 
    64   std::cout << "phase 0: " << max_flow_test.time-pre_time 
    65 	    << " sec"<< std::endl; 
    66   std::cout << "phase 1: " << post_time-max_flow_test.time 
    67 	    << " sec"<< std::endl; 
    68   std::cout << "flow value: "<< max_flow_test.maxFlow() << 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<< std::endl;
    73 
    74   
    75   return 0;
    76 }