ceph/src/boost/libs/graph/example/undirected_dfs.cpp

   1 //=======================================================================
   2 // Copyright 2002 Jeremy G. Siek, Andrew Lumsdaine, Lie-Quan Lee,
   3 //
   4 // Distributed under the Boost Software License, Version 1.0. (See
   5 // accompanying file LICENSE_1_0.txt or copy at
   6 // http://www.boost.org/LICENSE_1_0.txt)
   7 //=======================================================================
   8
   9 #include <string>
  10 #include <boost/graph/adjacency_list.hpp>
  11 #include <boost/graph/undirected_dfs.hpp>
  12 #include <boost/cstdlib.hpp>
  13 #include <iostream>
  14
  15 /*
  16   Example graph from Tarjei Knapstad.
  17
  18                    H15
  19                    |
  20           H8       C2
  21             \     /  \
  22           H9-C0-C1    C3-O7-H14
  23             /   |     |
  24           H10   C6    C4
  25                /  \  /  \
  26               H11  C5    H13
  27                    |
  28                    H12
  29 */
  30
  31 std::string name[] = { "C0", "C1", "C2", "C3", "C4", "C5", "C6", "O7",
  32                        "H8", "H9", "H10", "H11", "H12", "H13", "H14", "H15"};
  33
  34
  35 struct detect_loops : public boost::dfs_visitor<>
  36 {
  37   template <class Edge, class Graph>
  38   void back_edge(Edge e, const Graph& g) {
  39     std::cout << name[source(e, g)]
  40               << " -- "
  41               << name[target(e, g)] << "\n";
  42   }
  43 };
  44
  45 int main(int, char*[])
  46 {
  47   using namespace boost;
  48   typedef adjacency_list< vecS, vecS, undirectedS,
  49     no_property,
  50     property<edge_color_t, default_color_type> > graph_t;
  51   typedef graph_traits<graph_t>::vertex_descriptor vertex_t;
  52
  53   const std::size_t N = sizeof(name)/sizeof(std::string);
  54   graph_t g(N);
  55
  56   add_edge(0, 1, g);
  57   add_edge(0, 8, g);
  58   add_edge(0, 9, g);
  59   add_edge(0, 10, g);
  60   add_edge(1, 2, g);
  61   add_edge(1, 6, g);
  62   add_edge(2, 15, g);
  63   add_edge(2, 3, g);
  64   add_edge(3, 7, g);
  65   add_edge(3, 4, g);
  66   add_edge(4, 13, g);
  67   add_edge(4, 5, g);
  68   add_edge(5, 12, g);
  69   add_edge(5, 6, g);
  70   add_edge(6, 11, g);
  71   add_edge(7, 14, g);
  72
  73   std::cout << "back edges:\n";
  74   detect_loops vis;
  75   undirected_dfs(g, root_vertex(vertex_t(0)).visitor(vis)
  76                  .edge_color_map(get(edge_color, g)));
  77   std::cout << std::endl;
  78
  79   return boost::exit_success;
  80 }