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arXiv · 1607.08176

Suffix arrays with a twist

Tomasz Kowalski·Szymon Grabowski·Kimmo Fredriksson·Marcin Raniszewski
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Abstract

The suffix array is a classic full-text index, combining effectiveness with simplicity. We discuss three approaches aiming to improve its efficiency even more: changes to the navigation, data layout and adding extra data. In short, we show that $(i)$ how we search for the right interval boundary impacts significantly the overall search speed, $(ii)$ a B-tree data layout easily wins over the standard one, $(iii)$ the well-known idea of a lookup table for the prefixes of the suffixes can be refined with using compression, $(iv)$ caching prefixes of the suffixes in a helper array can pose a(nother) practical space-time tradeoff.

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Tomasz Kowalski, Szymon Grabowski, Kimmo Fredriksson, Marcin Raniszewski. 2016-07-27. Suffix arrays with a twist. https://arxiv.org/abs/1607.08176

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