Ethan Kim <ethkim <at> gmail.com> writes:
Hi all,The long standing question I've had for BGL is how to easily convert a
graph (using adjacency_list) from listS as vertex list to vecS. (And vice versa) I understand why there needs to be 2 different implementations depending on different uses of algorithms. But is there an easy way to convert them back and forth?Any tip would be much appreciated.Thanks,
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Do you mean given Graph A using listS you want to produce Graph B using vecS? How about something like this: template<class GraphFrom,class GraphTo> void foo(const GraphFrom& from,GraphTo& to) { typedef typename GraphFrom::vertex_iterator viter; typedef typename GraphFrom::vertex_descriptor vdesc; typedef typename GraphFrom::edge_iterator eiter; typedef std::map<viter,typename GraphTo::vertex_iterator> map_t; map_t table; viter vi,vend; //copy vertices for(tie(vi,vend)=from.vertices(); vi!=vend; ++vi) table[*vi] = add_vertex(to); eiter ei,eend; //copy edges for(tie(ei,eend)=from.edges(); ei!=eend; ++ei) { vdesc s = source(*ei,from); vdesc t = target(*ei,from); add_edge(table[s],table[t]); } } Assuming my template mangling is correct, this should produce an isomorphic graph of the corresponding type in about O( VlgV + ElgE ) time. Justin