Improved results for directed multicut

We give a simple algorithm for the Minimum Directed Multicut problem, and show that it gives an <i>O</i>(√<i>n</i>)-approximation. This improves on the previous approximation guarantee of <i>O</i>(√<i>n</i> log <i>k</i>) of Cheriyan, Karloff and Rabani [1], which was obtained by a more sophisticated algorithm.

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[2]  Yuval Rabani,et al.  Approximating Directed Multicuts , 2001, Proceedings 2001 IEEE International Conference on Cluster Computing.

[3]  David B. Shmoys,et al.  Cut problems and their application to divide-and-conquer , 1996 .