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arXiv · 2610.33229

Optimal Worst-Case Open Addressing: Braided Cuckoo Hashing

Andrew Krapivin·William Kuszmaul
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Abstract

In this paper, we introduce braided cuckoo hashing, an open-addressed hash table that supports load factor up to $1 - \varepsilon$ (for some parameter $\varepsilon \in (0, 1)$), while supporting queries, insertions, and deletions in worst-case time $O(\log \varepsilon^{-1})$, with high probability. This result represents an exponential improvement on insertion/deletion time over previous constructions, and disproves a conjecture of Bender, Kuszmaul, and Zhou that the product of worst-case query time and expected insertion/deletion time must be $Ω(\varepsilon^{-1})$.

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Andrew Krapivin, William Kuszmaul. 2026-10-23. Optimal Worst-Case Open Addressing: Braided Cuckoo Hashing. https://arxiv.org/abs/2610.33229

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