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arXiv · 1911.09077

Grammar Compressed Sequences with Rank/Select Support

Alberto Ordóñez·Gonzalo Navarro·Nieves R. Brisaboa
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Abstract

Sequence representations supporting not only direct access to their symbols, but also rank/select operations, are a fundamental building block in many compressed data structures. Several recent applications need to represent highly repetitive sequences, and classical statistical compression proves ineffective. We introduce, instead, grammar-based representations for repetitive sequences, which use up to 6% of the space needed by statistically compressed representations, and support direct access and rank/select operations within tens of microseconds. We demonstrate the impact of our structures in text indexing applications.

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Alberto Ordóñez, Gonzalo Navarro, Nieves R. Brisaboa. 2019-11-20. Grammar Compressed Sequences with Rank/Select Support. https://doi.org/10.1016/j.jda.2016.10.001

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