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arXiv · 2105.12407

Recognition of Linear and Star Variants of Leaf Powers is in P

Benjamin Bergougnoux·Svein Høgemo·Jan Arne Telle·Martin Vatshelle
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Abstract

A $k$-leaf power of a tree $T$ is a graph $G$ whose vertices are the leaves of $T$ and whose edges connect pairs of leaves whose distance in $T$ is at most $k$. A graph is a leaf power if it is a $k$-leaf power for some $k$. Over 20 years ago, Nishimura et al. [J. Algorithms, 2002] asked if recognition of leaf powers was in P. Recently, Lafond [SODA 2022] showed an XP algorithm when parameterized by $k$, while leaving the main question open. In this paper, we explore this question from the perspective of two alternative models of leaf powers, showing that both a linear and a star variant of leaf powers can be recognized in polynomial-time.

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Benjamin Bergougnoux, Svein Høgemo, Jan Arne Telle, Martin Vatshelle. 2021-05-26. Recognition of Linear and Star Variants of Leaf Powers is in P. https://arxiv.org/abs/2105.12407

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