As we know, now there is efficient algorithms to find the overall min-cut in a directed graph, e.g. Hao and Orlin (1994).* E# I% J' W) X! c3 Q- P* u
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Now my problem is to find an overall min-cut just separating some given node pairs, not all the node pairs. For example, I have an 8-node digraph with capacities on each arc and want to find the overall min-cut separating some node pairs such as 8 and 1, 6 and 3, 7 and 1. The algorithm of Hao and Orlin (1994) cannot solve my problem. + |3 b4 \% Z/ p. P* }* @) {5 i7 {" y/ W- E+ i3 @