Re: [Boost-users] [BGL] DistanceMatrix type for johnson_all_pairs_shortest_paths

...

const int V(num_vertices(g)); std::vector < int >d(V, (std::numeric_limits < int >::max)()); int D[V][V]; johnson_all_pairs_shortest_paths(g, D, distance_map(&d[0]));

But this didn't compile, I got the error

error: no matching function for call to ‘johnson_all_pairs_shortest_paths(Graph&, int [(long int)V][(long int)V], boost::bgl_named_params)’

I do not know how GCC handles the types of run-time sized arrays, which are compiler-specific in C++.

That's what the problem is... I couldn't see it. You can't instantiate a template over the type of a variable length array. You can probably think of it as a local type (a struct within a function), but it probably goes beyond that. Last time I checked, calling typeid on e.g., D resulted in a compiler error. That may have been GCC 4.1, though. Didn't GCC drop them at some point? This holds for linear arrays also. One more argument against variable length arrays. Andrew Sutton andrew.n.sutton@gmail.com