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arXiv · 2212.00946

Trie-Compressed Intersectable Sets

Diego Arroyuelo·Juan Pablo Castillo
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Abstract

We introduce space- and time-efficient algorithms and data structures for the offline set intersection problem. We show that a sorted integer set $S \subseteq [0{..}u)$ of $n$ elements can be represented using compressed space while supporting $k$-way intersections in adaptive $O(k\delta\lg{\!(u/\delta)})$ time, $\delta$ being the alternation measure introduced by Barbay and Kenyon. Our experimental results suggest that our approaches are competitive in practice, outperforming the most efficient alternatives (Partitioned Elias-Fano indexes, Roaring Bitmaps, and Recursive Universe Partitioning (RUP)) in several scenarios, offering in general relevant space-time trade-offs.

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Diego Arroyuelo, Juan Pablo Castillo. 2022-12-02. Trie-Compressed Intersectable Sets. https://arxiv.org/abs/2212.00946

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