A note on the Covering Steiner Problem
نویسندگان
چکیده
A randomized approximation algorithm for the undirected and directed covering Steiner Problems is presented. The algorithm is based on a randomized reduction to a problem called 12 -Group Steiner. For the undirected case, the approximation ratio matches the approximation ratio of Konjevod et al. [KRS01]. However, our approach is a lot simpler. For the directed covering Steiner this gives an O(n ) approximation for every constant > 0 and is the first non-trivial approximation for the problem. ∗Dept. of Electrical Engineering-Systems, Tel-Aviv University, Tel-Aviv 69978, Israel. E-mail:[email protected]. †Dept. of Computer Science, Rutgers Camden, NJ, USA. E-mail:[email protected]. ‡Computer Science Dept., Technische Universität Wien, A-1040 Wien, Austria. E-mail:[email protected].
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