Approximation Algorithms for k-Connected Graph Factors
نویسندگان
چکیده
Finding low-cost spanning subgraphs with given degree and connectivity requirements is a fundamental problem in the area of network design. We consider the problem of finding d-regular spanning subgraphs (or d-factors) of minimum weight with connectivity requirements. For the case of k-edge-connectedness, we present approximation algorithms that achieve constant approximation ratios for all d ≥ 2 · dk/2e. For the case of k-vertex-connectedness, we achieve constant approximation ratios for d ≥ 2k − 1. Our algorithms also work for arbitrary degree sequences if the minimum degree is at least 2 · dk/2e (for k-edgeconnectivity) or 2k − 1 (for k-vertex-connectivity).
منابع مشابه
2 PRELIMINARIES AND DEFINITIONS Vertex
Given a k vertex connected graph with weighted edges, we study the problem of nding a minimum weight spanning subgraph which is k vertex-connected, for k = 2; 3; 4. The problem is known to be NP-hard for any k, even when edges have no weight, and various approximation algorithms have been proposed. The best approximation factors that have been obtained are 2; 3 and 25 6 , for the cases k = 2; 3...
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