A 2 + ǫ approximation algorithm for the k-MST problem
نویسندگان
چکیده
For any ǫ > 0 we give a (2+ǫ)-approximation algorithm for the problem of finding a minimum tree spanning any k vertices in a graph (k-MST), improving a 3-approximation algorithm by Garg [5]. As in [5] the algorithm extends to a (2+ǫ)-approximation algorithm for the minimum tour that visits any k vertices, provided the edge costs satisfy the triangle inequality.
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