A unified algorithm for colouring graphs of bounded clique-width

Bruno Courcelle; Irène Durand; Michael Raskin

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arXiv · 2008.07468

A unified algorithm for colouring graphs of bounded clique-width

Bruno Courcelle·Irène Durand·Michael Raskin

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Abstract

Clique-width is one of the graph complexity measures leading to polynomial special-case algorithms for generally NP-complete problems, e.g. graph colourability. The best two currently known algorithms for verifying c-colourability of graphs represented as clique-width terms are optimised towards two different extreme cases, a constant number of colours and a very large number of colours. We present a way to unify these approaches in a single relatively simple algorithm that achieves the state of the art complexity in both cases. The unified algorithm also provides a speed-up for a large number of colours.

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Bruno Courcelle, Irène Durand, Michael Raskin. 2020-08-17. A unified algorithm for colouring graphs of bounded clique-width. https://arxiv.org/abs/2008.07468

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