Finding big matchings in planar graphs quickly

Therese Biedl

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arXiv · 1902.07812

Finding big matchings in planar graphs quickly

Therese Biedl

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Abstract

It is well-known that every $n$-vertex planar graph with minimum degree 3 has a matching of size at least $\frac{n}{3}$. But all proofs of this use the Tutte-Berge-formula for the size of a maximum matching. Hence these proofs are not directly algorithmic, and to find such a matching one must apply a general-purposes maximum matching algorithm, which has run-time $O(n^{1.5}\alpha(n))$ for planar graphs. In contrast to this, this paper gives a linear-time algorithm that finds a matching of size at least $\frac{n}{3}$ in any planar graph with minimum degree 3.

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Therese Biedl. 2019-02-20. Finding big matchings in planar graphs quickly. https://arxiv.org/abs/1902.07812

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