Approximating the selected-internal Steiner tree
نویسندگان
چکیده
In this paper, we consider a variant of the well-known Steiner tree problem. Given a complete graph G = (V, E) with a cost function c : E → R and two subsets R and R satisfying R ⊂ R ⊆ V , a selected-internal Steiner tree is a Steiner tree which contains (or spans) all the vertices in R such that each vertex in R cannot be a leaf. The selected-internal Steiner tree problem is to find a selected-internal Steiner tree with the minimum cost. In this paper, we present a 2ρ-approximation algorithm for the problem, where ρ is the best-known approximation ratio for the Steiner tree problem. c © 2007 Elsevier B.V. All rights reserved.
منابع مشابه
(1 + ρ)-Approximation for Selected-Internal Steiner Minimum Tree
Selected-internal Steiner minimum tree problem is a generalization of original Steiner minimum tree problem. Given a weighted complete graph G = (V,E) with weight function c, and two subsets R ′ ( R ⊆ V with |R − R ′ | ≥ 2, selected-internal Steiner minimum tree problem is to find a Steiner minimum tree T of G spanning R such that any leaf of T does not belong to R ′ . In this paper, suppose c ...
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ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 381 شماره
صفحات -
تاریخ انتشار 2007