src/work/marci/preflow_bug.cc
changeset 909 6a22e0dfd453
child 921 818510fa3d99
equal deleted inserted replaced
-1:000000000000 0:7ed016d9eeab
       
     1 // -*- c++ -*-
       
     2 #include <iostream>
       
     3 #include <fstream>
       
     4 
       
     5 #include <sage_graph.h>
       
     6 #include <hugo/smart_graph.h>
       
     7 #include <hugo/dimacs.h>
       
     8 //#include <hugo/time_measure.h>
       
     9 //#include <graph_wrapper.h>
       
    10 #include <hugo/max_flow.h>
       
    11 //#include <preflow_res.h>
       
    12 #include <for_each_macros.h>
       
    13 #include <graph_concept.h>
       
    14 
       
    15 using std::cout;
       
    16 using std::endl;
       
    17 
       
    18 using namespace hugo;
       
    19 
       
    20 // Use a DIMACS min cost flow file as stdin.
       
    21 // read_dimacs_demo < dimacs_max_flow_file
       
    22 
       
    23 int main(int, char **) {
       
    24 
       
    25   //typedef SageGraph MutableGraph;
       
    26   //typedef FullFeatureGraphConcept Graph;
       
    27   //typedef SmartGraph Graph;
       
    28   typedef SageGraph Graph;
       
    29   typedef Graph::Node Node;
       
    30   typedef Graph::EdgeIt EdgeIt;
       
    31 
       
    32   Graph g;
       
    33 
       
    34   Node s, t;
       
    35   Graph::EdgeMap<int> cap(g);
       
    36   Graph::EdgeMap<int> flow(g); //0 flow
       
    37   //readDimacs(std::cin, g, cap, s, t);
       
    38   readDimacs(std::cin, g, cap, s, t, flow);
       
    39 //  Timer ts;
       
    40   MaxFlow<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> > 
       
    41     max_flow_test(g, s, t, cap, flow);
       
    42   
       
    43   Graph::NodeMap<bool> cut(g);
       
    44 
       
    45   {
       
    46     Graph::EdgeIt e;
       
    47     for (g.first(e); g.valid(e); g.next(e))
       
    48       cout << 1+g.id(g.tail(e)) << "->" << 1+g.id(g.head(e)) << " cap: " << cap[e] << " preflow: " << flow[e] << endl;
       
    49   }
       
    50   {
       
    51     Graph::NodeIt n;
       
    52     for (g.first(n); g.valid(n); g.next(n)) {
       
    53       int a=0;
       
    54       {
       
    55 	Graph::InEdgeIt e;
       
    56 	for (g.first(e, n); g.valid(e); g.next(e)) a+=flow[e];
       
    57       }
       
    58       {
       
    59 	Graph::OutEdgeIt e;
       
    60 	for (g.first(e, n); g.valid(e); g.next(e)) a-=flow[e];
       
    61       }
       
    62       cout << 1+g.id(n) << " excess: " << a << endl;
       
    63     }
       
    64   }
       
    65 
       
    66 
       
    67   {
       
    68 //    std::cout << "preflow ..." << std::endl;
       
    69 //    ts.reset();
       
    70     max_flow_test.preflowPhase1(MaxFlow<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> >::PRE_FLOW);
       
    71 //    std::cout << "elapsed time: " << ts << std::endl;
       
    72     std::cout << "flow value: "<< max_flow_test.flowValue() << std::endl;
       
    73     std::cout << "flow value 2: "<< max_flow_test.flowValue2() << std::endl;
       
    74     max_flow_test.actMinCut(cut);
       
    75     
       
    76     Graph::EdgeIt e;
       
    77     for (g.first(e); g.valid(e); g.next(e)) {
       
    78       if (cut[g.tail(e)] && !cut[g.head(e)]) {
       
    79 	cout << 1+g.id(g.tail(e)) << "->" << 1+g.id(g.head(e)) 
       
    80 	     << "(forward edge) flow: " << flow[e] 
       
    81 	     << " cap: " << cap[e]<< endl;
       
    82 	if (flow[e]!=cap[e]) 
       
    83 	std::cout << "Slackness does not hold!" << std::endl;
       
    84       }
       
    85       if (!cut[g.tail(e)] && cut[g.head(e)]) {
       
    86 	cout << 1+g.id(g.tail(e)) << "->" << 1+g.id(g.head(e)) 
       
    87 	     << "(backward edge) flow: " << flow[e] << endl;
       
    88 	if (flow[e]!=0) 
       
    89 	std::cout << "Slackness does not hold!" << std::endl;
       
    90       }
       
    91     }
       
    92     Graph::NodeIt n;
       
    93     for (g.first(n); g.valid(n); g.next(n)) {
       
    94       if (cut[n]) 
       
    95 	cout << "in cut: " << 1+g.id(n) << endl;
       
    96     }
       
    97   }
       
    98 
       
    99 //   {
       
   100 //     std::cout << "preflow ..." << std::endl;
       
   101 //     ts.reset();
       
   102 //     max_flow_test.run();
       
   103 //     std::cout << "elapsed time: " << ts << std::endl;
       
   104 //     std::cout << "flow value: "<< max_flow_test.flowValue() << std::endl;
       
   105 //     max_flow_test.actMinCut(cut);
       
   106 
       
   107 //     FOR_EACH_LOC(Graph::EdgeIt, e, g) {
       
   108 //       if (cut[g.tail(e)] && !cut[g.head(e)] && !flow[e]==cap[e]) 
       
   109 // 	std::cout << "Slackness does not hold!" << std::endl;
       
   110 //       if (!cut[g.tail(e)] && cut[g.head(e)] && flow[e]>0) 
       
   111 // 	std::cout << "Slackness does not hold!" << std::endl;
       
   112 //     }
       
   113 //   }
       
   114 
       
   115 //   {
       
   116 //     std::cout << "preflow ..." << std::endl;
       
   117 //     FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0);
       
   118 //     ts.reset();
       
   119 //     max_flow_test.preflow(MaxFlow<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> >::GEN_FLOW);
       
   120 //     std::cout << "elapsed time: " << ts << std::endl;
       
   121 //     std::cout << "flow value: "<< max_flow_test.flowValue() << std::endl;
       
   122 
       
   123 //     FOR_EACH_LOC(Graph::EdgeIt, e, g) {
       
   124 //       if (cut[g.tail(e)] && !cut[g.head(e)] && !flow[e]==cap[e]) 
       
   125 // 	std::cout << "Slackness does not hold!" << std::endl;
       
   126 //       if (!cut[g.tail(e)] && cut[g.head(e)] && flow[e]>0) 
       
   127 // 	std::cout << "Slackness does not hold!" << std::endl;
       
   128 //     }
       
   129 //   }
       
   130 
       
   131 // //   {
       
   132 // //     std::cout << "wrapped preflow ..." << std::endl;
       
   133 // //     FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0);
       
   134 // //     ts.reset();
       
   135 // //     pre_flow_res.run();
       
   136 // //     std::cout << "elapsed time: " << ts << std::endl;
       
   137 // //     std::cout << "flow value: "<< pre_flow_test.flowValue() << std::endl;
       
   138 // //   }
       
   139 
       
   140 //   {
       
   141 //     std::cout << "physical blocking flow augmentation ..." << std::endl;
       
   142 //     FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0);
       
   143 //     ts.reset();
       
   144 //     int i=0;
       
   145 //     while (augmenting_flow_test.augmentOnBlockingFlow<MutableGraph>()) { ++i; }
       
   146 //     std::cout << "elapsed time: " << ts << std::endl;
       
   147 //     std::cout << "number of augmentation phases: " << i << std::endl; 
       
   148 //     std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl;
       
   149 
       
   150 //     FOR_EACH_LOC(Graph::EdgeIt, e, g) {
       
   151 //       if (cut[g.tail(e)] && !cut[g.head(e)] && !flow[e]==cap[e]) 
       
   152 // 	std::cout << "Slackness does not hold!" << std::endl;
       
   153 //       if (!cut[g.tail(e)] && cut[g.head(e)] && flow[e]>0) 
       
   154 // 	std::cout << "Slackness does not hold!" << std::endl;
       
   155 //     }
       
   156 //   }
       
   157 
       
   158 // //   {
       
   159 // //     std::cout << "faster physical blocking flow augmentation ..." << std::endl;
       
   160 // //     FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0);
       
   161 // //     ts.reset();
       
   162 // //     int i=0;
       
   163 // //     while (max_flow_test.augmentOnBlockingFlow1<MutableGraph>()) { ++i; }
       
   164 // //     std::cout << "elapsed time: " << ts << std::endl;
       
   165 // //     std::cout << "number of augmentation phases: " << i << std::endl; 
       
   166 // //     std::cout << "flow value: "<< max_flow_test.flowValue() << std::endl;
       
   167 // //   }
       
   168 
       
   169 //   {
       
   170 //     std::cout << "on-the-fly blocking flow augmentation ..." << std::endl;
       
   171 //     FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0);
       
   172 //     ts.reset();
       
   173 //     int i=0;
       
   174 //     while (augmenting_flow_test.augmentOnBlockingFlow2()) { ++i; }
       
   175 //     std::cout << "elapsed time: " << ts << std::endl;
       
   176 //     std::cout << "number of augmentation phases: " << i << std::endl; 
       
   177 //     std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl;
       
   178 
       
   179 //     FOR_EACH_LOC(Graph::EdgeIt, e, g) {
       
   180 //       if (cut[g.tail(e)] && !cut[g.head(e)] && !flow[e]==cap[e]) 
       
   181 // 	std::cout << "Slackness does not hold!" << std::endl;
       
   182 //       if (!cut[g.tail(e)] && cut[g.head(e)] && flow[e]>0) 
       
   183 // 	std::cout << "Slackness does not hold!" << std::endl;
       
   184 //     }
       
   185 //   }
       
   186 
       
   187 //   {
       
   188 //     std::cout << "on-the-fly shortest path augmentation ..." << std::endl;
       
   189 //     FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0);
       
   190 //     ts.reset();
       
   191 //     int i=0;
       
   192 //     while (augmenting_flow_test.augmentOnShortestPath()) { ++i; }
       
   193 //     std::cout << "elapsed time: " << ts << std::endl;
       
   194 //     std::cout << "number of augmentation phases: " << i << std::endl; 
       
   195 //     std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl;
       
   196 
       
   197 //     FOR_EACH_LOC(Graph::EdgeIt, e, g) {
       
   198 //       if (cut[g.tail(e)] && !cut[g.head(e)] && !flow[e]==cap[e]) 
       
   199 // 	std::cout << "Slackness does not hold!" << std::endl;
       
   200 //       if (!cut[g.tail(e)] && cut[g.head(e)] && flow[e]>0) 
       
   201 // 	std::cout << "Slackness does not hold!" << std::endl;
       
   202 //     }
       
   203 //   }
       
   204 
       
   205 //   {
       
   206 //     std::cout << "on-the-fly shortest path augmentation ..." << std::endl;
       
   207 //     FOR_EACH_LOC(Graph::EdgeIt, e, g) flow.set(e, 0);
       
   208 //     ts.reset();
       
   209 //     int i=0;
       
   210 //     while (augmenting_flow_test.augmentOnShortestPath2()) { ++i; }
       
   211 //     std::cout << "elapsed time: " << ts << std::endl;
       
   212 //     std::cout << "number of augmentation phases: " << i << std::endl; 
       
   213 //     std::cout << "flow value: "<< augmenting_flow_test.flowValue() << std::endl;
       
   214 
       
   215 //     FOR_EACH_LOC(Graph::EdgeIt, e, g) {
       
   216 //       if (cut[g.tail(e)] && !cut[g.head(e)] && !flow[e]==cap[e]) 
       
   217 // 	std::cout << "Slackness does not hold!" << std::endl;
       
   218 //       if (!cut[g.tail(e)] && cut[g.head(e)] && flow[e]>0) 
       
   219 // 	std::cout << "Slackness does not hold!" << std::endl;
       
   220 //     }
       
   221 //   }
       
   222 
       
   223   return 0;
       
   224 }