Single Commodity-Flow Algorithms for Lifts of Graphic and Co-graphic Matroids
نویسندگان
چکیده
Consider a binary matroid M given by its matrix representation. We show that if M is a lift of a graphic or a cographic matroid, then in polynomial time we can either solve the single commodity flow problem for M or find an obstruction for which the Max-Flow MinCut relation does not hold. The key tool is an algorithmic version of Lehman’s Theorem for the set covering polyhedron.
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