Tighter Bounds for Graph Steiner Tree Approximation
نویسندگان
چکیده
منابع مشابه
Tighter Bounds for Graph Steiner Tree Approximation
The classical Steiner tree problem in weighted graphs seeks a minimum weight connected subgraph containing a given subset of the vertices (terminals). We present a new polynomialtime heuristic that achieves a best-known approximation ratio of 1 + ln 3 2 ≈ 1.55 for general graphs, and best-known approximation ratios of ≈ 1.28 for quasi-bipartite graphs (i.e., where no two non-terminals are adjac...
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The Steiner tree problem which is known to be NP-Complete is the following. Given a weighted undirected graph G = (V;E), and a set X V of terminals, the objective is to nd a tree of minimum cost which connects all the terminals. If the graph is directed, in addition to X, we are given a root r 2 V , and the objective is to nd a minimum cost arborescence which connects the root to each of the te...
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ژورنال
عنوان ژورنال: SIAM Journal on Discrete Mathematics
سال: 2005
ISSN: 0895-4801,1095-7146
DOI: 10.1137/s0895480101393155