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arXiv · 1811.09411

Your Rugby Mates Don't Need to Know your Colleagues: Triadic Closure with Edge Colors

Laurent Bulteau·Niels Grüttemeier·Christian Komusiewicz·Manuel Sorge
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Abstract

Given an undirected graph $G=(V,E)$ the NP-hard Strong Triadic Closure (STC) problem asks for a labeling of the edges as \emph{weak} and \emph{strong} such that at most $k$ edges are weak and for each induced $P_3$ in $G$ at least one edge is weak. In this work, we study the following generalizations of STC with $c$ different strong edge colors. In Multi-STC an induced $P_3$ may receive two strong labels as long as they are different. In Edge-List Multi-STC and Vertex-List Multi-STC we may additionally restrict the set of permitted colors for each edge of $G$. We show that, under the Exponential Time Hypothesis (ETH), Edge-List Multi-STC and Vertex-List Multi-STC cannot be solved in time $2^{o(|V|^2)}$. We then proceed with a parameterized complexity analysis in which we extend previous fixed-parameter tractability results and kernelizations for STC [Golovach et al., Algorithmica '20, Grüttemeier and Komusiewicz, Algorithmica '20] to the three variants with multiple edge colors or outline the limits of such an extension.

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Laurent Bulteau, Niels Grüttemeier, Christian Komusiewicz, Manuel Sorge. 2021-03-11. Your Rugby Mates Don't Need to Know your Colleagues: Triadic Closure with Edge Colors. https://arxiv.org/abs/1811.09411

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