//======================================================================= // Copyright 2001 Jeremy G. Siek, Andrew Lumsdaine, Lie-Quan Lee, // // Distributed under the Boost Software License, Version 1.0. (See // accompanying file LICENSE_1_0.txt or copy at // http://www.boost.org/LICENSE_1_0.txt) //======================================================================= #include #include #include #include #include #include #include #include #include #include using namespace boost; template class bacon_number_recorder : public default_bfs_visitor { public: bacon_number_recorder(DistanceMap dist) : d(dist) { } template void tree_edge(Edge e, const Graph& g) const { typename graph_traits::vertex_descriptor u = source(e, g), v = target(e, g); d[v] = d[u] + 1; } private: DistanceMap d; }; // Convenience function template < typename DistanceMap > bacon_number_recorder record_bacon_number(DistanceMap d) { return bacon_number_recorder < DistanceMap > (d); } int main() { std::ifstream datafile("./kevin-bacon.dat"); if (!datafile) { std::cerr << "No ./kevin-bacon.dat file" << std::endl; return EXIT_FAILURE; } typedef adjacency_list < vecS, vecS, undirectedS, property < vertex_name_t, std::string >, property < edge_name_t, std::string > > Graph; Graph g; typedef property_map < Graph, vertex_name_t >::type actor_name_map_t; actor_name_map_t actor_name = get(vertex_name, g); typedef property_map < Graph, edge_name_t >::type movie_name_map_t; movie_name_map_t connecting_movie = get(edge_name, g); typedef graph_traits < Graph >::vertex_descriptor Vertex; typedef std::map < std::string, Vertex > NameVertexMap; NameVertexMap actors; for (std::string line; std::getline(datafile, line);) { char_delimiters_separator < char >sep(false, "", ";"); tokenizer <> line_toks(line, sep); tokenizer <>::iterator i = line_toks.begin(); std::string actors_name = *i++; NameVertexMap::iterator pos; bool inserted; Vertex u, v; boost::tie(pos, inserted) = actors.insert(std::make_pair(actors_name, Vertex())); if (inserted) { u = add_vertex(g); actor_name[u] = actors_name; pos->second = u; } else u = pos->second; std::string movie_name = *i++; boost::tie(pos, inserted) = actors.insert(std::make_pair(*i, Vertex())); if (inserted) { v = add_vertex(g); actor_name[v] = *i; pos->second = v; } else v = pos->second; graph_traits < Graph >::edge_descriptor e; boost::tie(e, inserted) = add_edge(u, v, g); if (inserted) connecting_movie[e] = movie_name; } std::vector < int >bacon_number(num_vertices(g)); Vertex src = actors["Kevin Bacon"]; bacon_number[src] = 0; breadth_first_search(g, src, visitor(record_bacon_number(&bacon_number[0]))); graph_traits < Graph >::vertex_iterator i, end; for (boost::tie(i, end) = vertices(g); i != end; ++i) { std::cout << actor_name[*i] << " has a Bacon number of " << bacon_number[*i] << std::endl; } return 0; }