Hello, I wondered are there way to count connected components in the minimum spanning tree? Currently I just making copy of graph to be able to count and collect connected components are there more efficient way to do that? ______________________________ std::vector < Edge > spanning_tree; Graph graphMST; kruskal_minimum_spanning_tree(graphFOREST, std::back_inserter(spanning_tree)); for (std::vector < Edge >::iterator ei = spanning_tree.begin(); ei != spanning_tree.end(); ++ei) { if(get(edge_weight, graphFOREST, *ei)<1.0)//lets cut the MTS by given threshold add_edge(source(*ei, graphFOREST),target(*ei, graphFOREST),get(edge_weight, graphFOREST, *ei),graphMST); } num = connected_components(graphMST, &component[0]); // Use components... _______________________________ Thank you beforehand Arman.