Approximation and Complexity of k-Splittable Flows
نویسندگان
چکیده
Given a graph with a source and a sink node, the NP–hard maximum k–splittable flow (MkSF) problem is to find a flow of maximum value with a flow decomposition using at most k paths [6]. The multicommodity variant of this problem is a natural generalization of disjoint paths and unsplittable flow problems. Constructing a k–splittable flow requires two interdepending decisions. One has to decide on k paths (routing) and on the flow values on these paths (packing). We give efficient algorithms for computing exact and approximate solutions by decoupling the two decisions into a first packing step and a second routing step. Our main contributions are
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