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arXiv · 2509.17819

Theory Meets Practice for Bit Vectors Supporting Rank and Select

Florian Kurpicz·Niccolò Rigi-Luperti·Peter Sanders
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Abstract

Bit vectors with support for fast rank and select are a fundamental building block for compressed data structures. We close a gap between theory and practice by analyzing an important part of the design space and experimentally evaluating a sweet spot. The result is the first implementation of a rank and select data structure for bit vectors with worst-case constant query time, good practical performance, and a space-overhead of just 0.78%, i.e., between $4.5\times$ and $64.1\times$ less than previous implementations.

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Florian Kurpicz, Niccolò Rigi-Luperti, Peter Sanders. 2025-09-22. Theory Meets Practice for Bit Vectors Supporting Rank and Select. https://arxiv.org/abs/2509.17819

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