test/min_cost_arborescence_test.cc
author Balazs Dezso <deba@google.com>
Fri, 22 Jan 2021 10:55:32 +0100
changeset 1208 c6aa2cc1af04
parent 1084 8b2d4e5d96e4
permissions -rw-r--r--
Factor out recursion from weighted matching algorithms (#638)
     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) 2003-2013
     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 <set>
    21 #include <vector>
    22 #include <iterator>
    23 
    24 #include <lemon/smart_graph.h>
    25 #include <lemon/min_cost_arborescence.h>
    26 #include <lemon/lgf_reader.h>
    27 #include <lemon/concepts/digraph.h>
    28 
    29 #include "test_tools.h"
    30 
    31 using namespace lemon;
    32 using namespace std;
    33 
    34 const char test_lgf[] =
    35   "@nodes\n"
    36   "label\n"
    37   "0\n"
    38   "1\n"
    39   "2\n"
    40   "3\n"
    41   "4\n"
    42   "5\n"
    43   "6\n"
    44   "7\n"
    45   "8\n"
    46   "9\n"
    47   "@arcs\n"
    48   "     label  cost\n"
    49   "1 8  0      107\n"
    50   "0 3  1      70\n"
    51   "2 1  2      46\n"
    52   "4 1  3      28\n"
    53   "4 4  4      91\n"
    54   "3 9  5      76\n"
    55   "9 8  6      61\n"
    56   "8 1  7      39\n"
    57   "9 8  8      74\n"
    58   "8 0  9      39\n"
    59   "4 3  10     45\n"
    60   "2 2  11     34\n"
    61   "0 1  12     100\n"
    62   "6 3  13     95\n"
    63   "4 1  14     22\n"
    64   "1 1  15     31\n"
    65   "7 2  16     51\n"
    66   "2 6  17     29\n"
    67   "8 3  18     115\n"
    68   "6 9  19     32\n"
    69   "1 1  20     60\n"
    70   "0 3  21     40\n"
    71   "@attributes\n"
    72   "source 0\n";
    73 
    74 
    75 void checkMinCostArborescenceCompile()
    76 {
    77   typedef double VType;
    78   typedef concepts::Digraph Digraph;
    79   typedef concepts::ReadMap<Digraph::Arc, VType> CostMap;
    80   typedef Digraph::Node Node;
    81   typedef Digraph::Arc Arc;
    82   typedef concepts::WriteMap<Digraph::Arc, bool> ArbMap;
    83   typedef concepts::ReadWriteMap<Digraph::Node, Digraph::Arc> PredMap;
    84 
    85   typedef MinCostArborescence<Digraph, CostMap>::
    86             SetArborescenceMap<ArbMap>::
    87             SetPredMap<PredMap>::Create MinCostArbType;
    88 
    89   Digraph g;
    90   Node s, n;
    91   Arc e;
    92   VType c;
    93   bool b;
    94   ::lemon::ignore_unused_variable_warning(c,b);
    95   int i;
    96   CostMap cost;
    97   ArbMap arb;
    98   PredMap pred;
    99 
   100   MinCostArbType mcarb_test(g, cost);
   101   const MinCostArbType& const_mcarb_test = mcarb_test;
   102 
   103   mcarb_test
   104     .arborescenceMap(arb)
   105     .predMap(pred)
   106     .run(s);
   107 
   108   mcarb_test.init();
   109   mcarb_test.addSource(s);
   110   mcarb_test.start();
   111   n = mcarb_test.processNextNode();
   112   b = const_mcarb_test.emptyQueue();
   113   i = const_mcarb_test.queueSize();
   114 
   115   c = const_mcarb_test.arborescenceCost();
   116   b = const_mcarb_test.arborescence(e);
   117   e = const_mcarb_test.pred(n);
   118   const MinCostArbType::ArborescenceMap &am =
   119     const_mcarb_test.arborescenceMap();
   120   const MinCostArbType::PredMap &pm =
   121     const_mcarb_test.predMap();
   122   b = const_mcarb_test.reached(n);
   123   b = const_mcarb_test.processed(n);
   124 
   125   i = const_mcarb_test.dualNum();
   126   c = const_mcarb_test.dualValue();
   127   i = const_mcarb_test.dualSize(i);
   128   c = const_mcarb_test.dualValue(i);
   129 
   130   ::lemon::ignore_unused_variable_warning(am);
   131   ::lemon::ignore_unused_variable_warning(pm);
   132 }
   133 
   134 int main() {
   135   typedef SmartDigraph Digraph;
   136   DIGRAPH_TYPEDEFS(Digraph);
   137 
   138   typedef Digraph::ArcMap<double> CostMap;
   139 
   140   Digraph digraph;
   141   CostMap cost(digraph);
   142   Node source;
   143 
   144   std::istringstream is(test_lgf);
   145   digraphReader(digraph, is).
   146     arcMap("cost", cost).
   147     node("source", source).run();
   148 
   149   MinCostArborescence<Digraph, CostMap> mca(digraph, cost);
   150   mca.run(source);
   151 
   152   vector<pair<double, set<Node> > > dualSolution(mca.dualNum());
   153 
   154   for (int i = 0; i < mca.dualNum(); ++i) {
   155     dualSolution[i].first = mca.dualValue(i);
   156     for (MinCostArborescence<Digraph, CostMap>::DualIt it(mca, i);
   157          it != INVALID; ++it) {
   158       dualSolution[i].second.insert(it);
   159     }
   160   }
   161 
   162   for (ArcIt it(digraph); it != INVALID; ++it) {
   163     if (mca.reached(digraph.source(it))) {
   164       double sum = 0.0;
   165       for (int i = 0; i < int(dualSolution.size()); ++i) {
   166         if (dualSolution[i].second.find(digraph.target(it))
   167             != dualSolution[i].second.end() &&
   168             dualSolution[i].second.find(digraph.source(it))
   169             == dualSolution[i].second.end()) {
   170           sum += dualSolution[i].first;
   171         }
   172       }
   173       if (mca.arborescence(it)) {
   174         check(sum == cost[it], "Invalid dual solution");
   175       }
   176       check(sum <= cost[it], "Invalid dual solution");
   177     }
   178   }
   179 
   180 
   181   check(mca.dualValue() == mca.arborescenceCost(), "Invalid dual solution");
   182 
   183   check(mca.reached(source), "Invalid arborescence");
   184   for (ArcIt a(digraph); a != INVALID; ++a) {
   185     check(!mca.reached(digraph.source(a)) ||
   186           mca.reached(digraph.target(a)), "Invalid arborescence");
   187   }
   188 
   189   for (NodeIt n(digraph); n != INVALID; ++n) {
   190     if (!mca.reached(n)) continue;
   191     int cnt = 0;
   192     for (InArcIt a(digraph, n); a != INVALID; ++a) {
   193       if (mca.arborescence(a)) {
   194         check(mca.pred(n) == a, "Invalid arborescence");
   195         ++cnt;
   196       }
   197     }
   198     check((n == source ? cnt == 0 : cnt == 1), "Invalid arborescence");
   199   }
   200 
   201   Digraph::ArcMap<bool> arborescence(digraph);
   202   check(mca.arborescenceCost() ==
   203         minCostArborescence(digraph, cost, source, arborescence),
   204         "Wrong result of the function interface");
   205 
   206   return 0;
   207 }