Combining Two Worlds: Parameterised Approximation for Vertex Cover
نویسندگان
چکیده
We explore opportunities for parameterising constant factor approximation algorithms for vertex cover. We provide a simple algorithm that works on any approximation ratio of the form 2l+1 l+1 and has complexity that outperforms an algorithm by Bourgeois et al. derived from a sophisticated exact parameterised algorithm. In particular, for l = 1 (factor 1.5 approximation) our algorithm runs in time O∗(1.09k). Additionally, we present an improved polynomial-time approximation algorithm for graphs of average degree four.
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