Approximating the minmax rooted-tree cover in a tree

نویسندگان

  • Hiroshi Nagamochi
  • Kohei Okada
چکیده

Given an edge-weighted rooted tree T and a positive integer p ( n), where n is the number of vertices in T , we cover all vertices in T by a set of p subtrees each of which contains the root r of T . The minmax rooted-tree cover problem asks to find such a set of p subtrees so as to minimize the maximum weight of the subtrees in the set. In this paper, we propose an O(n) time (2 + ε)-approximation algorithm to the problem, where ε > 0 is a prescribed constant. © 2007 Elsevier B.V. All rights reserved.

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عنوان ژورنال:
  • Inf. Process. Lett.

دوره 104  شماره 

صفحات  -

تاریخ انتشار 2007