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arXiv · 1511.01137

A 7/3-Approximation for Feedback Vertex Sets in Tournaments

Matthias Mnich·Virginia Vassilevska Williams·László A. Végh
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Abstract

We consider the minimum-weight feedback vertex set problem in tournaments: given a tournament with non-negative vertex weights, remove a minimum-weight set of vertices that intersects all cycles. This problem is $\mathsf{NP}$-hard to solve exactly, and Unique Games-hard to approximate by a factor better than 2. We present the first $7/3$ approximation algorithm for this problem, improving on the previously best known ratio $5/2$ given by Cai et al. [FOCS 1998, SICOMP 2001].

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Matthias Mnich, Virginia Vassilevska Williams, László A. Végh. 2015-11-03. A 7/3-Approximation for Feedback Vertex Sets in Tournaments. https://arxiv.org/abs/1511.01137

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