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arXiv · 1606.06617

A Self-Index on Block Trees

Gonzalo Navarro
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Abstract

The Block Tree is a recently proposed data structure that reaches compression close to Lempel-Ziv while supporting efficient direct access to text substrings. In this paper we show how a self-index can be built on top of a Block Tree so that it provides efficient pattern searches while using space proportional to that of the original data structure. More precisely, if a Lempel-Ziv parse cuts a text of length $n$ into $z$ non-overlapping phrases, then our index uses $O(z\log(n/z))$ words and finds the $occ$ occurrences of a pattern of length $m$ in time $O(m\log n+occ\log^\epsilon n)$ for any constant $\epsilon>0$.

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Gonzalo Navarro. 2016-06-21. A Self-Index on Block Trees. https://arxiv.org/abs/1606.06617

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