//======================================================================= // Copyright 1997, 1998, 1999, 2000 University of Notre Dame. // Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek // // This file is part of the Boost Graph Library // // You should have received a copy of the License Agreement for the // Boost Graph Library along with the software; see the file LICENSE. // If not, contact Office of Research, University of Notre Dame, Notre // Dame, IN 46556. // // Permission to modify the code and to distribute modified code is // granted, provided the text of this NOTICE is retained, a notice that // the code was modified is included with the above COPYRIGHT NOTICE and // with the COPYRIGHT NOTICE in the LICENSE file, and that the LICENSE // file is distributed with the modified code. // // LICENSOR MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED. // By way of example, but not limitation, Licensor MAKES NO // REPRESENTATIONS OR WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY // PARTICULAR PURPOSE OR THAT THE USE OF THE LICENSED SOFTWARE COMPONENTS // OR DOCUMENTATION WILL NOT INFRINGE ANY PATENTS, COPYRIGHTS, TRADEMARKS // OR OTHER RIGHTS. //======================================================================= #include #include #include #include #include #include #include #include #include /* Sample Output: 0 --> 2 1 --> 1 3 4 2 --> 1 3 4 3 --> 1 4 4 --> 0 1 distances: 0 2 1 2 1 parent[0] = 0 parent[1] = 2 parent[2] = 0 parent[3] = 2 parent[4] = 0 */ template struct print_parent { print_parent(const ParentDecorator& p_) : p(p_) { } template void operator()(const Vertex& v) const { std::cout << "parent[" << v << "] = " << p[v] << std::endl; } ParentDecorator p; }; template class distance_and_pred_visitor : public boost::bfs_visitor<> { typedef typename boost::property_traits::value_type ColorValue; typedef boost::color_traits Color; public: distance_and_pred_visitor(DistanceMap d, PredecessorMap p, ColorMap c) : m_distance(d), m_predecessor(p), m_color(c) { } template void tree_edge(Edge e, const Graph& g) const { typename boost::graph_traits::vertex_descriptor u = source(e, g), v = target(e, g); if (get(m_color, v) == Color::white()) { put(m_distance, v, get(m_distance, u) + 1); put(m_predecessor, v, u); } else if (get(m_color, u) == Color::white()) { put(m_distance, u, get(m_distance, v) + 1); put(m_predecessor, u, v); } } DistanceMap m_distance; PredecessorMap m_predecessor; ColorMap m_color; }; int main(int , char* []) { typedef boost::adjacency_list< boost::mapS, boost::vecS, boost::bidirectionalS, boost::property > Graph; typedef boost::property_map::type ColorMap; Graph G(5); boost::add_edge(0, 2, G); boost::add_edge(1, 1, G); boost::add_edge(1, 3, G); boost::add_edge(1, 4, G); boost::add_edge(2, 1, G); boost::add_edge(2, 3, G); boost::add_edge(2, 4, G); boost::add_edge(3, 1, G); boost::add_edge(3, 4, G); boost::add_edge(4, 0, G); boost::add_edge(4, 1, G); typedef Graph::vertex_descriptor Vertex; // Array to store predecessor (parent) of each vertex. This will be // used as a Decorator (actually, its iterator will be). std::vector p(boost::num_vertices(G)); // VC++ version of std::vector has no ::pointer, so // I use ::value_type* instead. typedef std::vector::value_type* Piter; // Array to store distances from the source to each vertex . We use // a built-in array here just for variety. This will also be used as // a Decorator. typedef boost::graph_traits::vertices_size_type size_type; size_type d[5]; std::fill_n(d, 5, 0); // The source vertex Vertex s = *(boost::vertices(G).first); p[s] = s; distance_and_pred_visitor vis(d, &p[0], get(boost::vertex_color, G)); boost::neighbor_breadth_first_search (G, s, boost::visitor(vis). color_map(get(boost::vertex_color, G))); boost::print_graph(G); if (boost::num_vertices(G) < 11) { std::cout << "distances: "; #ifdef BOOST_OLD_STREAM_ITERATORS std::copy(d, d + 5, std::ostream_iterator(std::cout, " ")); #else std::copy(d, d + 5, std::ostream_iterator(std::cout, " ")); #endif std::cout << std::endl; std::for_each(boost::vertices(G).first, boost::vertices(G).second, print_parent(&p[0])); } return 0; }