On Cutting a Few Vertices from a Graph
نویسندگان
چکیده
We consider the problem of 0nding in an undirected graph a minimum cut that separates exactly a given number k of vertices. For general k (i.e. k is part of the input and may depend on n) this problem is NP-hard. We present for this problem a randomized approximation algorithm, which is useful when k is relatively small. In particular, for k = O(log n) we obtain a polynomial time approximation scheme, and for k = (log n) we obtain an approximation ratio O(k=log n). ? 2003 Elsevier Science B.V. All rights reserved.
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عنوان ژورنال:
- Discrete Applied Mathematics
دوره 127 شماره
صفحات -
تاریخ انتشار 2003