Dear All I would like some help with graph structure for the edmund_karp max flow min cut function. I have a general graph in which I have many properties + edge and vertex. I sould like to run edmund karp on this graph however I have not been able to make the structure right for edmund karp and therefore I have made a second graph a flow graph. However I do not want to copy edges over every time I change something in the original graph. I was wundering if I could make it the same graph or just make the flow graph a filteret version of the original graph. The graphs are defined as follows:: original:: typedef boost::adjacency_list Graph; typedef boost::graph_traits<Graph> DirectedTraits; typedef DirectedTraits::vertex_descriptor DirectedVertex; typedef DirectedTraits::edge_descriptor DirectedEdge; typedef DirectedTraits::vertex_iterator VertexIterator; typedef DirectedTraits::edge_iterator DirectedEdgeIterator; typedef DirectedTraits::out_edge_iterator DirectedOutEdgeIterator; typedef DirectedTraits::in_edge_iterator DirectedInEdgeIterator; typedef boost::property_map::type EdgeNameMap; flow graph:: typedef boost::adjacency_list_traits FlowTraits; typedef FlowTraits::edge_descriptor edge_descriptor; typedef FlowTraits::vertex_descriptor vertex_descriptor; typedef boost::adjacency_list > > > > FlowGraph; typedef boost::graph_traits<FlowGraph> DirectedFlowTraits; typedef DirectedFlowTraits::out_edge_iterator FlowOutEdgeIterator; typedef boost::property_map::type MaxEdgeWeightMap; Thanks for your help Line