Approximation Algorithms for the Unsplittable Flow Problem on Paths and Trees
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چکیده
We study the Unsplittable Flow Problem (UFP) and related variants, namely UFP with Bag Constraints and UFP with Rounds, on paths and trees. We provide improved constant factor approximation algorithms for all these problems under the no bottleneck assumption (NBA), which says that the maximum demand for any source-sink pair is at most the minimum capacity of any edge. We obtain these improved results by expressing a feasible solution to a natural LP relaxation of the UFP as a near-convex combination of feasible integral solutions. 1998 ACM Subject Classification F.2.2 Nonnumerical Algorithms and Problems
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تاریخ انتشار 2012