A 2-Approximation Algorithm for Finding an Optimum 3-Vertex-Connected Spanning Subgraph
نویسندگان
چکیده
منابع مشابه
A 2-Approximation Algorithm for Finding an Optimum 3-Vertex-Connected Spanning Subgraph
The problem of finding a minimum weight k-vertex connected spanning subgraph in a graph G = (V,E) is considered. For k ≥ 2, this problem is known to be NP-hard. Combining properties of inclusionminimal k-vertex connected graphs and of k-out-connected graphs (i.e., graphs which contain a vertex from which there exist k internally vertex-disjoint paths to every other vertex), we derive an auxilia...
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The problem of finding a minimum weight k-vertex connected spanning subgraph is considered. For k ≥ 2, this problem is known to be NP-hard. Combining properties of inclusion-minimal k-vertex connected graphs and of k-out-connected graphs (i.e., graphs which contain a vertex from which there exist k internally vertex-disjoint paths to every other vertex), we derive polynomial time approximation ...
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We present an O(log k)-approximation algorithm for the problem of finding a k-vertex connected spanning subgraph of minimum cost, where n is the number of vertices in an input graph, and k is a connectivity requirement. Our algorithm is the first that achieves a polylogarithmic approximation ratio for all values of k and n, and it works for both directed and undirected graphs. As in previous wo...
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We consider the following problem: given an integer k and a graph with a nonnegative cost function on its edges, nd its minimum weight k-vertex connected spanning subgraph. For k > 1, this problem is known to be NP-hard. For an arbitrary k, the best known approximation algorithm is due to Ravi and Williamson which achieves the approximation ratio 2H(k), where H (k) = 1 + 1 2 + : : : + 1 k is th...
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ژورنال
عنوان ژورنال: Journal of Algorithms
سال: 1999
ISSN: 0196-6774
DOI: 10.1006/jagm.1999.1006