COIN-OR::LEMON - Graph Library

source: lemon-0.x/src/work/marci/max_bipartite_matching_demo.cc @ 195:19f8bd411014

Last change on this file since 195:19f8bd411014 was 195:19f8bd411014, checked in by marci, 16 years ago

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File size: 3.6 KB
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[192]1// -*- c++ -*-
2#include <iostream>
3#include <fstream>
4#include <vector>
5#include <cstdlib>
6
7#include <LEDA/graph.h>
8#include <leda_graph_wrapper.h>
9#include <dimacs.h>
10#include <time_measure.h>
11#include <edmonds_karp.h>
12
13/**
14 * Inicializalja a veletlenszamgeneratort.
15 * Figyelem, ez nem jo igazi random szamokhoz,
16 * erre ne bizzad a titkaidat!
17 */
18void random_init()
19{
20        unsigned int seed = getpid();
21        seed |= seed << 15;
22        seed ^= time(0);
23
24        srand(seed);
25}
26
27/**
28 * Egy veletlen int-et ad vissza 0 es m-1 kozott.
29 */
30int random(int m)
31{
32        return int( double(m) * rand() / (RAND_MAX + 1.0) );
33}
34
35using namespace hugo;
36
37using std::cout;
38using std::endl;
39
40int main() {
41  leda::graph g;
42  typedef LedaGraphWrapper<leda::graph> Graph;
43  Graph G(g);
44
45  typedef Graph::Node Node;
46  typedef Graph::NodeIt NodeIt; 
47  typedef Graph::Edge Edge;
48  typedef Graph::EdgeIt EdgeIt;
49  typedef Graph::OutEdgeIt OutEdgeIt;
50  typedef Graph::InEdgeIt InEdgeIt;
51
[194]52  //Node s, t;
[192]53  //Graph::EdgeMap<int> cap(G);
54  //readDimacsMaxFlow(std::cin, G, s, t, cap);
55  std::vector<Node> s_nodes;
56  std::vector<Node> t_nodes;
57
[195]58  for(int i=0; i<4; ++i) {
[192]59    s_nodes.push_back(G.addNode());
60  }
[195]61  for(int i=0; i<4; ++i) {
[192]62    t_nodes.push_back(G.addNode());
63  }
[195]64//   random_init();
65//   for(int i=0; i<6; ++i) {
66//     G.addEdge(s_nodes[random(4)], t_nodes[random(4)]);
67//   }
68 
69  G.addEdge(s_nodes[2], t_nodes[4-4]);
70  G.addEdge(s_nodes[2], t_nodes[7-4]);
71  G.addEdge(s_nodes[2], t_nodes[4-4]);
72  G.addEdge(s_nodes[3], t_nodes[6-4]);
73  G.addEdge(s_nodes[3], t_nodes[5-4]);
74  G.addEdge(s_nodes[3], t_nodes[5-4]);
75
76
[194]77  Graph::NodeMap<bool> s_map(G); //false
78  Graph::NodeMap<bool> t_map(G); //false
[192]79 
[195]80  for(int i=0; i<4; ++i) {
[192]81    s_map.set(s_nodes[i], true);
82    t_map.set(t_nodes[i], true);
83  }
84
[195]85  cout << "bfs and dfs iterator demo on the directed graph" << endl;
86  for(NodeIt n=G.first<NodeIt>(); G.valid(n); G.next(n)) {
87    cout << G.id(n) << ": ";
88    cout << "out edges: ";
89    for(OutEdgeIt e=G.first<OutEdgeIt>(n); G.valid(e); G.next(e))
90      cout << G.id(G.tail(e)) << "->" << G.id(G.head(e)) << " ";
91    cout << "in edges: ";
92    for(InEdgeIt e=G.first<InEdgeIt>(n); G.valid(e); G.next(e))
93      cout << G.id(G.tail(e)) << "->" << G.id(G.head(e)) << " ";
94    cout << endl;
95  }
96
97
[192]98  {
99    std::cout << "on-the-fly max bipartite matching demo on wrapped leda graph..." << std::endl;
100    Graph::EdgeMap<int> flow(G); //0 flow
[194]101    Graph::EdgeMap<int> cap(G, 1);
[192]102
103    Timer ts;
104    ts.reset();
105
106    MaxMatching<Graph, int, Graph::EdgeMap<int>, Graph::EdgeMap<int> > max_flow_test(G, s_map, t_map, flow, cap);
107    //max_flow_test.augmentWithBlockingFlow<Graph>();
108    int i=0;
109    while (max_flow_test.augmentOnShortestPath()) {
110//     for(EdgeIt e=G.template first<EdgeIt>(); e.valid(); ++e) {
111//       std::cout<<"("<<G.tail(e)<< "-"<<flow.get(e)<<"->"<<G.head(e)<<") ";
112//     }
113//     std::cout<<std::endl;
114      ++i;
115    }
116
[195]117    std::cout << "maximum matching: "<< std::endl;
118    for(EdgeIt e=G.first<EdgeIt>(); G.valid(e); G.next(e)) 
119      if (flow.get(e))
120        std::cout << G.id(G.tail(e)) << "-" << flow.get(e) << "->" << G.id(G.head(e)) << " ";
121    std::cout<<std::endl;
122    std::cout << "edges which are not in this maximum matching: "<< std::endl;
123    for(EdgeIt e=G.first<EdgeIt>(); G.valid(e); G.next(e)) 
124      if (!flow.get(e))
125        std::cout << G.id(G.tail(e)) << "-" << flow.get(e) << "->" << G.id(G.head(e)) << " ";
126    std::cout<<std::endl;
127   
[192]128    std::cout << "elapsed time: " << ts << std::endl;
129    std::cout << "number of augmentation phases: " << i << std::endl;
130    std::cout << "flow value: "<< max_flow_test.flowValue() << std::endl;
131  }
132 
133
134  return 0;
135}
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