Hi, I used the edmunds_karp_max_flow algorithm in my project and it worked fine. Then I changed it to the push_relabel_max_flow algorithm but it doesn't work. I get an access violation at line 562 in the push_relabel_max_flow.hpp . Line 560: ai = out_edges(u, g).first; -> u is the node, that is directly connected with the source, when access violation occurs. Have anyone a suggestion where the problem could be? Thanks, Matthias