test/arborescence_test.cc
author deba
Fri, 03 Nov 2006 16:29:32 +0000
changeset 2293 1ee6e8788cc7
parent 2180 d5544c9409e4
child 2386 81b47fc5c444
permissions -rw-r--r--
First implementation of the static graph class
It could be improved to get better running times on benchmarks
     1 #include <iostream>
     2 #include <set>
     3 #include <vector>
     4 #include <iterator>
     5 
     6 #include <cmath>
     7 #include <cstdlib>
     8 
     9 #include <lemon/smart_graph.h>
    10 #include <lemon/min_cost_arborescence.h>
    11 
    12 #include <lemon/graph_utils.h>
    13 #include <lemon/time_measure.h>
    14 
    15 #include <lemon/tolerance.h>
    16 
    17 #include "test_tools.h"
    18 
    19 using namespace lemon;
    20 using namespace std;
    21 
    22 const int n = 10;
    23 const int e = 22;
    24 
    25 int sourceNode = 0;
    26 
    27 int sources[e] = {
    28   1, 0, 2, 4, 4, 3, 9, 8, 9, 8,
    29   4, 2, 0, 6, 4, 1, 7, 2, 8, 6,
    30   1, 0
    31 };
    32 
    33 int targets[e] = {
    34   8, 3, 1, 1, 4, 9, 8, 1, 8, 0,
    35   3, 2, 1, 3, 1, 1, 2, 6, 3, 9,
    36   1, 3
    37 };
    38 
    39 double costs[e] = {
    40   107.444, 70.3069, 46.0496, 28.3962, 91.4325,
    41   76.9443, 61.986, 39.3754, 74.9575, 39.3153,
    42   45.7094, 34.6184, 100.156, 95.726, 22.3429,
    43   31.587, 51.6972, 29.6773, 115.038, 32.4137,
    44   60.0038, 40.1237
    45 };
    46 
    47 
    48 
    49 int main() {
    50   typedef SmartGraph Graph;
    51   GRAPH_TYPEDEFS(Graph);
    52 
    53   typedef Graph::EdgeMap<double> CostMap;
    54 
    55   Graph graph;
    56   CostMap cost(graph);
    57   vector<Node> nodes;
    58   
    59   for (int i = 0; i < n; ++i) {
    60     nodes.push_back(graph.addNode());
    61   }
    62 
    63   for (int i = 0; i < e; ++i) {
    64     Edge edge = graph.addEdge(nodes[sources[i]], nodes[targets[i]]);
    65     cost[edge] = costs[i];
    66   }
    67 
    68   Node source = nodes[sourceNode];
    69 
    70   MinCostArborescence<Graph, CostMap> mca(graph, cost);
    71   mca.run(source);
    72 
    73   vector<pair<double, set<Node> > > dualSolution(mca.dualSize());
    74 
    75   for (int i = 0; i < mca.dualSize(); ++i) {
    76     dualSolution[i].first = mca.dualValue(i);
    77     for (MinCostArborescence<Graph, CostMap>::DualIt it(mca, i); 
    78          it != INVALID; ++it) {
    79       dualSolution[i].second.insert(it);
    80     }
    81   }
    82 
    83   Tolerance<double> tolerance;
    84 
    85   for (EdgeIt it(graph); it != INVALID; ++it) {
    86     if (mca.reached(graph.source(it))) {
    87       double sum = 0.0;
    88       for (int i = 0; i < (int)dualSolution.size(); ++i) {
    89         if (dualSolution[i].second.find(graph.target(it)) 
    90             != dualSolution[i].second.end() &&
    91             dualSolution[i].second.find(graph.source(it)) 
    92             == dualSolution[i].second.end()) {
    93           sum += dualSolution[i].first;
    94         }
    95       }
    96       if (mca.arborescence(it)) {
    97         check(!tolerance.less(sum, cost[it]), "INVALID DUAL");
    98       }
    99       check(!tolerance.less(cost[it], sum), "INVALID DUAL");
   100     }
   101   }
   102 
   103 
   104   check(!tolerance.different(mca.dualValue(), mca.arborescenceValue()),
   105                "INVALID DUAL");
   106 
   107 
   108   check(mca.reached(source), "INVALID ARBORESCENCE");
   109   for (EdgeIt it(graph); it != INVALID; ++it) {
   110     check(!mca.reached(graph.source(it)) || 
   111                  mca.reached(graph.target(it)), "INVALID ARBORESCENCE");
   112   }
   113 
   114   for (NodeIt it(graph); it != INVALID; ++it) {
   115     if (!mca.reached(it)) continue;
   116     int cnt = 0;
   117     for (InEdgeIt jt(graph, it); jt != INVALID; ++jt) {
   118       if (mca.arborescence(jt)) {
   119         ++cnt;
   120       }
   121     }
   122     check((it == source ? cnt == 0 : cnt == 1), "INVALID ARBORESCENCE");
   123   }
   124   
   125   return 0;
   126 }