On Sun, 2 Oct 2011, gongyiling wrote:
i 'm a newbie to boost graph library, I'm trying to compile a sample code as following:
struct demo_visitor : public boost::default_bfs_visitor { template <typename Vertex, typename Graph> void discover_vertex(Vertex v, Graph& g) { //std::cout<<g[v].url<<std::endl; } };
int main(int argc, char* argv[]) { typedef boost::adjacency_list<boost::vecS, boost::listS, //change this to boost::vecS compile ok. boost::directedS> graph_t; typedef boost::graph_traits<graph_t>::vertex_descriptor vertex_descriptor_t;
graph_t g; demo_visitor vis; boost::breadth_first_search(g, boost::vertex(0, g), boost::visitor(vis)); return 0; }
And it fail to compile will the error in two_bit_color_map.hpp: can't transfer boost::detail::error_property_not_found to size_t.
When I change the second type argument(VertexListS) of boost::adjacency_list from boost::listS to boost::vecS, it compile ok. Is there any implicite constraints on breadth_first_search? I also checked that boost::adjacency_list match the VertexListGraph concept both, using boost::vecS and boost::listS as it VertexListS type argument.
The breadth_first_search algorithm requires a property map for vertex indexes; that is supplied automatically when you use vecS as the vertex container but is not when you use listS. If you truly need listS, you will need to create a new vertex property named vertex_index (boost::vertex_index_t in graph declarations) and fill it in before you call the algorithm. You can fill it using a simple loop over the vertices, assigning consecutive numbers to them. -- Jeremiah Willcock