Re: [Boost-users] [BGL] Troubles with floyd_warshall_all_pairs, johnson_all_pairs

Hi, Doug! Thanks a lot for your reply, you've solved my issue. Best regards, Alex. "Doug Gregor" wrote in message news:D9C1BCC3-0FD1-490A-BEB6-02A7AEE13AE2@osl.iu.edu...

On Jul 2, 2007, at 6:26 AM, Alex Ivanov wrote:

...

//AFAIK it's impossible to declare array using directive below in runtime: double [xx][xx] D; //Compiler says the same: "C2057: expected constant expression" //even code: double [(const int)xx][(const int)xx] D; //won't work, so the only option left is to make a pointer: double* D = new [xx*xx] ;

//but both "floyd_warshall_all_pairs_shortest_paths" and "johnson_all_pairs_shortest_paths" are declared to take a reference, not a pointer, so you'll get multiple compile errors, if you try to compile like below:

floyd_warshall_all_pairs_shortest_paths(G, D);

The DistanceMatrix is expected to be subscripted twice, so you would need something like:

typedef double* double_array;

double_array* D = new double_array[xx]; for (int i = 0; i < xx; ++i) D[i] = new double [xx];

Or, you could use a vector of vectors:

vector D(xx, vector<double>(xx));

- Doug