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arXiv · 2107.03861

Feedback Vertex Set on Geometric Intersection Graphs

Shinwoo An·Eunjin Oh
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Abstract

In this paper, we present an algorithm for computing a feedback vertex set of a unit disk graph of size $k$, if it exists, which runs in time $2^{O(\sqrt{k})}(n+m)$, where $n$ and $m$ denote the numbers of vertices and edges, respectively. This improves the $2^{O(\sqrt{k}\log k)}n^{O(1)}$-time algorithm for this problem on unit disk graphs by Fomin et al. [ICALP 2017]. Moreover, our algorithm is optimal assuming the exponential-time hypothesis. Also, our algorithm can be extended to handle geometric intersection graphs of similarly sized fat objects without increasing the running time.

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Shinwoo An, Eunjin Oh. 2021-07-08. Feedback Vertex Set on Geometric Intersection Graphs. https://arxiv.org/abs/2107.03861

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