1 // (C) Copyright 2007-2009 Andrew Sutton
2 //
3 // Use, modification and distribution are subject to the
4 // Boost Software License, Version 1.0 (See accompanying file
5 // LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)
6
7 #include <iostream>
8
9 #include <boost/graph/graph_utility.hpp>
10 #include <boost/graph/undirected_graph.hpp>
11 #include <boost/graph/directed_graph.hpp>
12 #include <boost/graph/tiernan_all_cycles.hpp>
13 #include <boost/graph/erdos_renyi_generator.hpp>
14
15 #include <boost/random/linear_congruential.hpp>
16
17 using namespace std;
18 using namespace boost;
19
20 struct cycle_validator
21 {
cycle_validatorcycle_validator22 cycle_validator(size_t& c)
23 : cycles(c)
24 { }
25
26 template <typename Path, typename Graph>
cyclecycle_validator27 void cycle(const Path& p, const Graph& g)
28 {
29 ++cycles;
30 // Check to make sure that each of the vertices in the path
31 // is truly connected and that the back is connected to the
32 // front - it's not validating that we find all paths, just
33 // that the paths are valid.
34 typename Path::const_iterator i, j, last = prior(p.end());
35 for(i = p.begin(); i != last; ++i) {
36 j = boost::next(i);
37 BOOST_ASSERT(edge(*i, *j, g).second);
38 }
39 BOOST_ASSERT(edge(p.back(), p.front(), g).second);
40 }
41
42 size_t& cycles;
43 };
44
45 template <typename Graph>
test()46 void test()
47 {
48 typedef erdos_renyi_iterator<boost::minstd_rand, Graph> er;
49
50 // Generate random graphs with 15 vertices and 15% probability
51 // of edge connection.
52 static const size_t N = 20;
53 static const double P = 0.1;
54 boost::minstd_rand rng;
55
56 Graph g(er(rng, N, P), er(), N);
57 renumber_indices(g);
58 print_edges(g, get(vertex_index, g));
59
60 size_t cycles = 0;
61 cycle_validator vis(cycles);
62 tiernan_all_cycles(g, vis);
63 cout << "# cycles: " << vis.cycles << "\n";
64 }
65
66 int
main(int,char * [])67 main(int, char *[])
68 {
69 typedef undirected_graph<> Graph;
70 typedef directed_graph<> DiGraph;
71
72 std::cout << "*** undirected ***\n";
73 test<Graph>();
74
75 std::cout << "*** directed ***\n";
76 test<DiGraph>();
77 }
78