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arXiv · 2611.04186

Incremental Open Addressing Has No Time-Space Tradeoff

Martín Farach-Colton·Andrew Krapivin·William Kuszmaul
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Abstract

In this paper, we show that there is no time-space tradeoff in incremental open addressing: there is an incremental open-addressed hash table that supports $O(1)$ worst-case expected time insertions, positive queries, and negative queries, at any load factor (even load factor $1$). As an intermediate result, we also revisit the problem of constructing an incremental open-addressed hash table that does not perform reordering (does not move elements around over time). In this setting, we show that it is possible to get $O(1)$ amortized expected positive query time together with $O(1)$ worst-case expected insertion time, a combination that was not previously known to be possible.

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Martín Farach-Colton, Andrew Krapivin, William Kuszmaul. 2026-11-03. Incremental Open Addressing Has No Time-Space Tradeoff. https://arxiv.org/abs/2611.04186

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