n)-Approximation Algorithm For Directed Sparsest Cut
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چکیده
We give an O( √ n)-approximation algorithm for the Sparsest Cut Problem on directed graphs. A näıve reduction from Sparsest Cut to Minimum Multicut would only give an approximation ratio of O( √ n log D), where D is the sum of the demands. We obtain the improvement using a novel LP-rounding method for fractional Sparsest Cut, the dual of Maximum Concurrent Flow.
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تاریخ انتشار 2005