A note on the longest common Abelian factor problem

Szymon Grabowski

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arXiv · 1503.01093

A note on the longest common Abelian factor problem

Szymon Grabowski

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Abstract

Abelian string matching problems are becoming an object of considerable interest in last years. Very recently, Alatabbi et al. \cite{AILR2015} presented the first solution for the longest common Abelian factor problem for a pair of strings, reaching $O(\sigma n^2)$ time with $O(\sigma n \log n)$ bits of space, where $n$ is the length of the strings and $\sigma$ is the alphabet size. In this note we show how the time complexity can be preserved while the space is reduced by a factor of $\sigma$, and then how the time complexity can be improved, if the alphabet is not too small, when superlinear space is allowed.

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Szymon Grabowski. 2015-03-03. A note on the longest common Abelian factor problem. https://arxiv.org/abs/1503.01093

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