ceph/src/boost/libs/graph/test/tiernan_all_cycles.cpp

   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 {
  22     cycle_validator(size_t& c)
  23         : cycles(c)
  24     { }
  25
  26     template <typename Path, typename Graph>
  27     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>
  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
  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 }