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arXiv · 2201.06773

Computing Longest (Common) Lyndon Subsequences

Hideo Bannai·Tomohiro I·Tomasz Kociumaka·Dominik Köppl·Simon J. Puglisi
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Abstract

Given a string $T$ with length $n$ whose characters are drawn from an ordered alphabet of size $\sigma$, its longest Lyndon subsequence is a longest subsequence of $T$ that is a Lyndon word. We propose algorithms for finding such a subsequence in $O(n^3)$ time with $O(n)$ space, or online in $O(n^3 \sigma)$ space and time. Our first result can be extended to find the longest common Lyndon subsequence of two strings of length $n$ in $O(n^4 \sigma)$ time using $O(n^3)$ space.

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Hideo Bannai, Tomohiro I, Tomasz Kociumaka, Dominik Köppl, Simon J. Puglisi. 2022-01-18. Computing Longest (Common) Lyndon Subsequences. https://arxiv.org/abs/2201.06773

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