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arXiv · 2408.11225

Approximately covering vertices by order-$5$ or longer paths

Mingyang Gong·Zhi-Zhong Chen·Guohui Lin·Lusheng Wang
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Abstract

This paper studies $MPC^{5+}_v$, which is to cover as many vertices as possible in a given graph $G=(V,E)$ by vertex-disjoint $5^+$-paths (i.e., paths each with at least five vertices). $MPC^{5+}_v$ is NP-hard and admits an existing local-search-based approximation algorithm which achieves a ratio of $\frac {19}7\approx 2.714$ and runs in $O(|V|^6)$ time. In this paper, we present a new approximation algorithm for $MPC^{5+}_v$ which achieves a ratio of $2.511$ and runs in $O(|V|^{2.5} |E|^2)$ time. Unlike the previous algorithm, the new algorithm is based on maximum matching, maximum path-cycle cover, and recursion.

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Mingyang Gong, Zhi-Zhong Chen, Guohui Lin, Lusheng Wang. 2024-08-20. Approximately covering vertices by order-$5$ or longer paths. https://arxiv.org/abs/2408.11225

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