Constant-Factor Approximation for TSP with Disks

Adrian Dumitrescu; Csaba D. Tóth

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arXiv · 1506.07903

Constant-Factor Approximation for TSP with Disks

Adrian Dumitrescu·Csaba D. Tóth

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Abstract

We revisit the traveling salesman problem with neighborhoods (TSPN) and present the first constant-ratio approximation for disks in the plane: Given a set of $n$ disks in the plane, a TSP tour whose length is at most $O(1)$ times the optimal can be computed in time that is polynomial in $n$. Our result is the first constant-ratio approximation for a class of planar convex bodies of arbitrary size and arbitrary intersections. In order to achieve a $O(1)$-approximation, we reduce the traveling salesman problem with disks, up to constant factors, to a minimum weight hitting set problem in a geometric hypergraph. The connection between TSPN and hitting sets in geometric hypergraphs, established here, is likely to have future applications.

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BibTeX RIS

Adrian Dumitrescu, Csaba D. Tóth. 2016-08-09. Constant-Factor Approximation for TSP with Disks. https://arxiv.org/abs/1506.07903

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