test/max_matching_test.cc
author Peter Kovacs <kpeter@inf.elte.hu>
Wed, 15 Apr 2009 12:01:14 +0200
changeset 590 b61354458b59
parent 440 88ed40ad0d4f
child 593 7ac52d6a268e
permissions -rw-r--r--
Imporvements for the matching algorithms (#264)
     1 /* -*- mode: C++; indent-tabs-mode: nil; -*-
     2  *
     3  * This file is a part of LEMON, a generic C++ optimization library.
     4  *
     5  * Copyright (C) 2003-2009
     6  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
     7  * (Egervary Research Group on Combinatorial Optimization, EGRES).
     8  *
     9  * Permission to use, modify and distribute this software is granted
    10  * provided that this copyright notice appears in all copies. For
    11  * precise terms see the accompanying LICENSE file.
    12  *
    13  * This software is provided "AS IS" with no warranty of any kind,
    14  * express or implied, and with no claim as to its suitability for any
    15  * purpose.
    16  *
    17  */
    18 
    19 #include <iostream>
    20 #include <sstream>
    21 #include <vector>
    22 #include <queue>
    23 #include <cstdlib>
    24 
    25 #include <lemon/max_matching.h>
    26 #include <lemon/smart_graph.h>
    27 #include <lemon/concepts/graph.h>
    28 #include <lemon/concepts/maps.h>
    29 #include <lemon/lgf_reader.h>
    30 #include <lemon/math.h>
    31 
    32 #include "test_tools.h"
    33 
    34 using namespace std;
    35 using namespace lemon;
    36 
    37 GRAPH_TYPEDEFS(SmartGraph);
    38 
    39 
    40 const int lgfn = 3;
    41 const std::string lgf[lgfn] = {
    42   "@nodes\n"
    43   "label\n"
    44   "0\n"
    45   "1\n"
    46   "2\n"
    47   "3\n"
    48   "4\n"
    49   "5\n"
    50   "6\n"
    51   "7\n"
    52   "@edges\n"
    53   "     label  weight\n"
    54   "7 4  0      984\n"
    55   "0 7  1      73\n"
    56   "7 1  2      204\n"
    57   "2 3  3      583\n"
    58   "2 7  4      565\n"
    59   "2 1  5      582\n"
    60   "0 4  6      551\n"
    61   "2 5  7      385\n"
    62   "1 5  8      561\n"
    63   "5 3  9      484\n"
    64   "7 5  10     904\n"
    65   "3 6  11     47\n"
    66   "7 6  12     888\n"
    67   "3 0  13     747\n"
    68   "6 1  14     310\n",
    69 
    70   "@nodes\n"
    71   "label\n"
    72   "0\n"
    73   "1\n"
    74   "2\n"
    75   "3\n"
    76   "4\n"
    77   "5\n"
    78   "6\n"
    79   "7\n"
    80   "@edges\n"
    81   "     label  weight\n"
    82   "2 5  0      710\n"
    83   "0 5  1      241\n"
    84   "2 4  2      856\n"
    85   "2 6  3      762\n"
    86   "4 1  4      747\n"
    87   "6 1  5      962\n"
    88   "4 7  6      723\n"
    89   "1 7  7      661\n"
    90   "2 3  8      376\n"
    91   "1 0  9      416\n"
    92   "6 7  10     391\n",
    93 
    94   "@nodes\n"
    95   "label\n"
    96   "0\n"
    97   "1\n"
    98   "2\n"
    99   "3\n"
   100   "4\n"
   101   "5\n"
   102   "6\n"
   103   "7\n"
   104   "@edges\n"
   105   "     label  weight\n"
   106   "6 2  0      553\n"
   107   "0 7  1      653\n"
   108   "6 3  2      22\n"
   109   "4 7  3      846\n"
   110   "7 2  4      981\n"
   111   "7 6  5      250\n"
   112   "5 2  6      539\n",
   113 };
   114 
   115 void checkMaxMatchingCompile()
   116 {
   117   typedef concepts::Graph Graph;
   118   typedef Graph::Node Node;
   119   typedef Graph::Edge Edge;
   120   typedef Graph::EdgeMap<bool> MatMap;
   121 
   122   Graph g;
   123   Node n;
   124   Edge e;
   125   MatMap mat(g);
   126 
   127   MaxMatching<Graph> mat_test(g);
   128   const MaxMatching<Graph>&
   129     const_mat_test = mat_test;
   130 
   131   mat_test.init();
   132   mat_test.greedyInit();
   133   mat_test.matchingInit(mat);
   134   mat_test.startSparse();
   135   mat_test.startDense();
   136   mat_test.run();
   137   
   138   const_mat_test.matchingSize();
   139   const_mat_test.matching(e);
   140   const_mat_test.matching(n);
   141   const_mat_test.mate(n);
   142 
   143   MaxMatching<Graph>::Status stat = 
   144     const_mat_test.decomposition(n);
   145   const_mat_test.barrier(n);
   146   
   147   ignore_unused_variable_warning(stat);
   148 }
   149 
   150 void checkMaxWeightedMatchingCompile()
   151 {
   152   typedef concepts::Graph Graph;
   153   typedef Graph::Node Node;
   154   typedef Graph::Edge Edge;
   155   typedef Graph::EdgeMap<int> WeightMap;
   156 
   157   Graph g;
   158   Node n;
   159   Edge e;
   160   WeightMap w(g);
   161 
   162   MaxWeightedMatching<Graph> mat_test(g, w);
   163   const MaxWeightedMatching<Graph>&
   164     const_mat_test = mat_test;
   165 
   166   mat_test.init();
   167   mat_test.start();
   168   mat_test.run();
   169   
   170   const_mat_test.matchingValue();
   171   const_mat_test.matchingSize();
   172   const_mat_test.matching(e);
   173   const_mat_test.matching(n);
   174   const_mat_test.mate(n);
   175   
   176   int k = 0;
   177   const_mat_test.dualValue();
   178   const_mat_test.nodeValue(n);
   179   const_mat_test.blossomNum();
   180   const_mat_test.blossomSize(k);
   181   const_mat_test.blossomValue(k);
   182 }
   183 
   184 void checkMaxWeightedPerfectMatchingCompile()
   185 {
   186   typedef concepts::Graph Graph;
   187   typedef Graph::Node Node;
   188   typedef Graph::Edge Edge;
   189   typedef Graph::EdgeMap<int> WeightMap;
   190 
   191   Graph g;
   192   Node n;
   193   Edge e;
   194   WeightMap w(g);
   195 
   196   MaxWeightedPerfectMatching<Graph> mat_test(g, w);
   197   const MaxWeightedPerfectMatching<Graph>&
   198     const_mat_test = mat_test;
   199 
   200   mat_test.init();
   201   mat_test.start();
   202   mat_test.run();
   203   
   204   const_mat_test.matchingValue();
   205   const_mat_test.matching(e);
   206   const_mat_test.matching(n);
   207   const_mat_test.mate(n);
   208   
   209   int k = 0;
   210   const_mat_test.dualValue();
   211   const_mat_test.nodeValue(n);
   212   const_mat_test.blossomNum();
   213   const_mat_test.blossomSize(k);
   214   const_mat_test.blossomValue(k);
   215 }
   216 
   217 void checkMatching(const SmartGraph& graph,
   218                    const MaxMatching<SmartGraph>& mm) {
   219   int num = 0;
   220 
   221   IntNodeMap comp_index(graph);
   222   UnionFind<IntNodeMap> comp(comp_index);
   223 
   224   int barrier_num = 0;
   225 
   226   for (NodeIt n(graph); n != INVALID; ++n) {
   227     check(mm.decomposition(n) == MaxMatching<SmartGraph>::EVEN ||
   228           mm.matching(n) != INVALID, "Wrong Gallai-Edmonds decomposition");
   229     if (mm.decomposition(n) == MaxMatching<SmartGraph>::ODD) {
   230       ++barrier_num;
   231     } else {
   232       comp.insert(n);
   233     }
   234   }
   235 
   236   for (EdgeIt e(graph); e != INVALID; ++e) {
   237     if (mm.matching(e)) {
   238       check(e == mm.matching(graph.u(e)), "Wrong matching");
   239       check(e == mm.matching(graph.v(e)), "Wrong matching");
   240       ++num;
   241     }
   242     check(mm.decomposition(graph.u(e)) != MaxMatching<SmartGraph>::EVEN ||
   243           mm.decomposition(graph.v(e)) != MaxMatching<SmartGraph>::MATCHED,
   244           "Wrong Gallai-Edmonds decomposition");
   245 
   246     check(mm.decomposition(graph.v(e)) != MaxMatching<SmartGraph>::EVEN ||
   247           mm.decomposition(graph.u(e)) != MaxMatching<SmartGraph>::MATCHED,
   248           "Wrong Gallai-Edmonds decomposition");
   249 
   250     if (mm.decomposition(graph.u(e)) != MaxMatching<SmartGraph>::ODD &&
   251         mm.decomposition(graph.v(e)) != MaxMatching<SmartGraph>::ODD) {
   252       comp.join(graph.u(e), graph.v(e));
   253     }
   254   }
   255 
   256   std::set<int> comp_root;
   257   int odd_comp_num = 0;
   258   for (NodeIt n(graph); n != INVALID; ++n) {
   259     if (mm.decomposition(n) != MaxMatching<SmartGraph>::ODD) {
   260       int root = comp.find(n);
   261       if (comp_root.find(root) == comp_root.end()) {
   262         comp_root.insert(root);
   263         if (comp.size(n) % 2 == 1) {
   264           ++odd_comp_num;
   265         }
   266       }
   267     }
   268   }
   269 
   270   check(mm.matchingSize() == num, "Wrong matching");
   271   check(2 * num == countNodes(graph) - (odd_comp_num - barrier_num),
   272          "Wrong matching");
   273   return;
   274 }
   275 
   276 void checkWeightedMatching(const SmartGraph& graph,
   277                    const SmartGraph::EdgeMap<int>& weight,
   278                    const MaxWeightedMatching<SmartGraph>& mwm) {
   279   for (SmartGraph::EdgeIt e(graph); e != INVALID; ++e) {
   280     if (graph.u(e) == graph.v(e)) continue;
   281     int rw = mwm.nodeValue(graph.u(e)) + mwm.nodeValue(graph.v(e));
   282 
   283     for (int i = 0; i < mwm.blossomNum(); ++i) {
   284       bool s = false, t = false;
   285       for (MaxWeightedMatching<SmartGraph>::BlossomIt n(mwm, i);
   286            n != INVALID; ++n) {
   287         if (graph.u(e) == n) s = true;
   288         if (graph.v(e) == n) t = true;
   289       }
   290       if (s == true && t == true) {
   291         rw += mwm.blossomValue(i);
   292       }
   293     }
   294     rw -= weight[e] * mwm.dualScale;
   295 
   296     check(rw >= 0, "Negative reduced weight");
   297     check(rw == 0 || !mwm.matching(e),
   298           "Non-zero reduced weight on matching edge");
   299   }
   300 
   301   int pv = 0;
   302   for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) {
   303     if (mwm.matching(n) != INVALID) {
   304       check(mwm.nodeValue(n) >= 0, "Invalid node value");
   305       pv += weight[mwm.matching(n)];
   306       SmartGraph::Node o = graph.target(mwm.matching(n));
   307       check(mwm.mate(n) == o, "Invalid matching");
   308       check(mwm.matching(n) == graph.oppositeArc(mwm.matching(o)),
   309             "Invalid matching");
   310     } else {
   311       check(mwm.mate(n) == INVALID, "Invalid matching");
   312       check(mwm.nodeValue(n) == 0, "Invalid matching");
   313     }
   314   }
   315 
   316   int dv = 0;
   317   for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) {
   318     dv += mwm.nodeValue(n);
   319   }
   320 
   321   for (int i = 0; i < mwm.blossomNum(); ++i) {
   322     check(mwm.blossomValue(i) >= 0, "Invalid blossom value");
   323     check(mwm.blossomSize(i) % 2 == 1, "Even blossom size");
   324     dv += mwm.blossomValue(i) * ((mwm.blossomSize(i) - 1) / 2);
   325   }
   326 
   327   check(pv * mwm.dualScale == dv * 2, "Wrong duality");
   328 
   329   return;
   330 }
   331 
   332 void checkWeightedPerfectMatching(const SmartGraph& graph,
   333                           const SmartGraph::EdgeMap<int>& weight,
   334                           const MaxWeightedPerfectMatching<SmartGraph>& mwpm) {
   335   for (SmartGraph::EdgeIt e(graph); e != INVALID; ++e) {
   336     if (graph.u(e) == graph.v(e)) continue;
   337     int rw = mwpm.nodeValue(graph.u(e)) + mwpm.nodeValue(graph.v(e));
   338 
   339     for (int i = 0; i < mwpm.blossomNum(); ++i) {
   340       bool s = false, t = false;
   341       for (MaxWeightedPerfectMatching<SmartGraph>::BlossomIt n(mwpm, i);
   342            n != INVALID; ++n) {
   343         if (graph.u(e) == n) s = true;
   344         if (graph.v(e) == n) t = true;
   345       }
   346       if (s == true && t == true) {
   347         rw += mwpm.blossomValue(i);
   348       }
   349     }
   350     rw -= weight[e] * mwpm.dualScale;
   351 
   352     check(rw >= 0, "Negative reduced weight");
   353     check(rw == 0 || !mwpm.matching(e),
   354           "Non-zero reduced weight on matching edge");
   355   }
   356 
   357   int pv = 0;
   358   for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) {
   359     check(mwpm.matching(n) != INVALID, "Non perfect");
   360     pv += weight[mwpm.matching(n)];
   361     SmartGraph::Node o = graph.target(mwpm.matching(n));
   362     check(mwpm.mate(n) == o, "Invalid matching");
   363     check(mwpm.matching(n) == graph.oppositeArc(mwpm.matching(o)),
   364           "Invalid matching");
   365   }
   366 
   367   int dv = 0;
   368   for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) {
   369     dv += mwpm.nodeValue(n);
   370   }
   371 
   372   for (int i = 0; i < mwpm.blossomNum(); ++i) {
   373     check(mwpm.blossomValue(i) >= 0, "Invalid blossom value");
   374     check(mwpm.blossomSize(i) % 2 == 1, "Even blossom size");
   375     dv += mwpm.blossomValue(i) * ((mwpm.blossomSize(i) - 1) / 2);
   376   }
   377 
   378   check(pv * mwpm.dualScale == dv * 2, "Wrong duality");
   379 
   380   return;
   381 }
   382 
   383 
   384 int main() {
   385 
   386   for (int i = 0; i < lgfn; ++i) {
   387     SmartGraph graph;
   388     SmartGraph::EdgeMap<int> weight(graph);
   389 
   390     istringstream lgfs(lgf[i]);
   391     graphReader(graph, lgfs).
   392       edgeMap("weight", weight).run();
   393 
   394     MaxMatching<SmartGraph> mm(graph);
   395     mm.run();
   396     checkMatching(graph, mm);
   397 
   398     MaxWeightedMatching<SmartGraph> mwm(graph, weight);
   399     mwm.run();
   400     checkWeightedMatching(graph, weight, mwm);
   401 
   402     MaxWeightedPerfectMatching<SmartGraph> mwpm(graph, weight);
   403     bool perfect = mwpm.run();
   404 
   405     check(perfect == (mm.matchingSize() * 2 == countNodes(graph)),
   406           "Perfect matching found");
   407 
   408     if (perfect) {
   409       checkWeightedPerfectMatching(graph, weight, mwpm);
   410     }
   411   }
   412 
   413   return 0;
   414 }