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arXiv · 1909.06231

Characterising circular-arc contact $B_0$-VPG graphs

Flavia Bonomo-Braberman·Esther Galby·Carolina Lucía Gonzalez
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Abstract

A contact $B_0$-VPG graph is a graph for which there exists a collection of nontrivial pairwise interiorly disjoint horizontal and vertical segments in one-to-one correspondence with its vertex set such that two vertices are adjacent if and only if the corresponding segments touch. It was shown by Deniz et al. that Recognition is $\mathsf{NP}$-complete for contact $B_0$-VPG graphs. In this paper we present a minimal forbidden induced subgraph characterisation of contact $B_0$-VPG graphs within the class of circular-arc graphs and provide a polynomial-time algorithm for recognising these graphs.

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Flavia Bonomo-Braberman, Esther Galby, Carolina Lucía Gonzalez. 2019-09-13. Characterising circular-arc contact $B_0$-VPG graphs. https://doi.org/10.1016/j.dam.2020.01.027

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