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arXiv · 1911.03542

Space Efficient Construction of Lyndon Arrays in Linear Time

Philip Bille·Jonas Ellert·Johannes Fischer·Inge Li Gørtz·Florian Kurpicz·Ian Munro·Eva Rotenberg
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Abstract

We present the first linear time algorithm to construct the $2n$-bit version of the Lyndon array for a string of length $n$ using only $o(n)$ bits of working space. A simpler variant of this algorithm computes the plain ($n\lg n$-bit) version of the Lyndon array using only $\mathcal{O}(1)$ words of additional working space. All previous algorithms are either not linear, or use at least $n\lg n$ bits of additional working space. Also in practice, our new algorithms outperform the previous best ones by an order of magnitude, both in terms of time and space.

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Philip Bille, Jonas Ellert, Johannes Fischer, Inge Li Gørtz, Florian Kurpicz, Ian Munro, Eva Rotenberg. 2019-11-08. Space Efficient Construction of Lyndon Arrays in Linear Time. https://arxiv.org/abs/1911.03542

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