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arXiv · 2406.00221

Counting on General Run-Length Grammars

Gonzalo Navarro·Alejandro Pacheco
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Abstract

We introduce a data structure for counting pattern occurrences in texts compressed with any run-length context-free grammar. Our structure uses space proportional to the grammar size and counts the occurrences of a pattern of length $m$ in a text of length $n$ in time \(O(m\log^{2+ε} n)\), for any constant \(ε> 0\) chosen at indexing time. This is the first solution to an open problem posed by Christiansen et al.~[ACM TALG 2020] and enhances our abilities for computation over compressed data; we give an example application.

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Gonzalo Navarro, Alejandro Pacheco. 2025-01-28. Counting on General Run-Length Grammars. https://arxiv.org/abs/2406.00221

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