1 // Copyright (c) 2006, Stephan Diederich
2 //
3 // This code may be used under either of the following two licences:
4 //
5 // Permission is hereby granted, free of charge, to any person
6 // obtaining a copy of this software and associated documentation
7 // files (the "Software"), to deal in the Software without
8 // restriction, including without limitation the rights to use,
9 // copy, modify, merge, publish, distribute, sublicense, and/or
10 // sell copies of the Software, and to permit persons to whom the
11 // Software is furnished to do so, subject to the following
12 // conditions:
13 //
14 // The above copyright notice and this permission notice shall be
15 // included in all copies or substantial portions of the Software.
16 //
17 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
19 // OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
21 // HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
22 // WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
23 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
24 // OTHER DEALINGS IN THE SOFTWARE. OF SUCH DAMAGE.
25 //
26 // Or:
27 //
28 // Distributed under the Boost Software License, Version 1.0.
29 // (See accompanying file LICENSE_1_0.txt or copy at
30 // http://www.boost.org/LICENSE_1_0.txt)
31
32 #include <vector>
33 #include <iterator>
34 #include <iostream>
35 #include <algorithm>
36 #include <fstream>
37
38 #include <boost/core/lightweight_test.hpp>
39 // three max_flows we test here
40 #include <boost/graph/boykov_kolmogorov_max_flow.hpp>
41 #include <boost/graph/push_relabel_max_flow.hpp>
42 #include <boost/graph/edmonds_karp_max_flow.hpp>
43 // boost utilities we use
44 #include <boost/graph/adjacency_list.hpp>
45 #include <boost/graph/random.hpp>
46 #include <boost/property_map/property_map.hpp>
47 #include <boost/random/linear_congruential.hpp>
48 #include <boost/lexical_cast.hpp>
49
50 /***************
51 * test which compares results of the three different max_flow implementations
52 * command line parameters:
53 * number_of_vertices: defaults to 100
54 * number_of_edges: defaults to 1000
55 * seeed: defaults to 1
56 ***************/
57
58 using namespace boost;
59
main(int argc,char * argv[])60 int main(int argc, char* argv[])
61 {
62
63 typedef adjacency_list_traits< vecS, vecS, directedS > Traits;
64 typedef adjacency_list< vecS, vecS, directedS,
65 property< vertex_index_t, long,
66 property< vertex_color_t, boost::default_color_type,
67 property< vertex_distance_t, long,
68 property< vertex_predecessor_t,
69 Traits::edge_descriptor > > > >,
70 property< edge_capacity_t, long,
71 property< edge_residual_capacity_t, long,
72 property< edge_reverse_t, Traits::edge_descriptor > > > >
73 Graph;
74
75 typedef graph_traits< Graph >::edge_descriptor tEdge;
76 typedef graph_traits< Graph >::vertex_descriptor tVertex;
77
78 graph_traits< Graph >::vertices_size_type n_verts = 100;
79 graph_traits< Graph >::edges_size_type n_edges = 1000;
80 std::size_t seed = 1;
81
82 if (argc > 1)
83 n_verts = lexical_cast< std::size_t >(argv[1]);
84 if (argc > 2)
85 n_edges = lexical_cast< std::size_t >(argv[2]);
86 if (argc > 3)
87 seed = lexical_cast< std::size_t >(argv[3]);
88
89 Graph g;
90 const int cap_low = 1;
91 const int cap_high = 1000;
92
93 // init random numer generator
94 minstd_rand gen(seed);
95 // generate graph
96 generate_random_graph(g, n_verts, n_edges, gen);
97
98 // init an uniform distribution int generator
99 typedef variate_generator< minstd_rand, uniform_int< int > > tIntGen;
100 tIntGen int_gen(gen, uniform_int< int >(cap_low, cap_high));
101 // init edge-capacities
102 randomize_property< edge_capacity_t, Graph, tIntGen >(g, int_gen);
103
104 // get source and sink node
105 tVertex source_vertex = random_vertex(g, gen);
106 tVertex sink_vertex = graph_traits< Graph >::null_vertex();
107 while (sink_vertex == graph_traits< Graph >::null_vertex()
108 || sink_vertex == source_vertex)
109 sink_vertex = random_vertex(g, gen);
110
111 // add reverse edges (ugly... how to do better?!)
112 property_map< Graph, edge_reverse_t >::type rev = get(edge_reverse, g);
113 property_map< Graph, edge_capacity_t >::type cap = get(edge_capacity, g);
114 std::list< tEdge > edges_copy;
115 graph_traits< Graph >::edge_iterator ei, e_end;
116 boost::tie(ei, e_end) = edges(g);
117 std::copy(
118 ei, e_end, std::back_insert_iterator< std::list< tEdge > >(edges_copy));
119 while (!edges_copy.empty())
120 {
121 tEdge old_edge = edges_copy.front();
122 edges_copy.pop_front();
123 tVertex source_vertex = target(old_edge, g);
124 tVertex target_vertex = source(old_edge, g);
125 bool inserted;
126 tEdge new_edge;
127 boost::tie(new_edge, inserted)
128 = add_edge(source_vertex, target_vertex, g);
129 assert(inserted);
130 rev[old_edge] = new_edge;
131 rev[new_edge] = old_edge;
132 cap[new_edge] = 0;
133 }
134
135 typedef property_traits< property_map< Graph,
136 edge_capacity_t >::const_type >::value_type tEdgeVal;
137
138 tEdgeVal bk = boykov_kolmogorov_max_flow(g, source_vertex, sink_vertex);
139 tEdgeVal push_relabel
140 = push_relabel_max_flow(g, source_vertex, sink_vertex);
141 tEdgeVal edmonds_karp
142 = edmonds_karp_max_flow(g, source_vertex, sink_vertex);
143
144 BOOST_TEST(bk == push_relabel);
145 BOOST_TEST(push_relabel == edmonds_karp);
146
147 return boost::report_errors();
148 }
149