Upper Bounds for Vertex Cover Further Improved
نویسندگان
چکیده
The problem instance of Vertex Cover consists of an undirected graph G = (V, E) and a positive integer k, the question is whether there exists a subset C ⊆ V of vertices such that each edge in E has at least one of its endpoints in C with |C| ≤ k. We improve two recent worst case upper bounds for Vertex Cover. First, Balasubramanian et al. showed that Vertex Cover can be solved in time O(kn + 1.32472k), where n is the number of vertices in G. Afterwards, Downey et al. improved this to O(kn + 1.31951k). Bringing the exponential base significantly below 1.3, we present the new upper bound O(kn + 1.29175k). We also show how to modify the algorithm to get O(kn + 1.29175) as an upper bound, a technique that is also applicable to the two preceeding algorithms mentioned above. Improved Upper Bounds for Vertex Cover 3
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