The Bathroom Model: A Realistic Approach to Hash Table Algorithm Optimization

Qiantong Wang

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arXiv · 2502.10977

The Bathroom Model: A Realistic Approach to Hash Table Algorithm Optimization

Qiantong Wang

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Abstract

Hash table search strategies have remained a pivotal area of inquiry in computer science over the past several decades. A prevailing viewpoint asserts that random probing stands as the optimal method for open-addressing hash tables. Challenging this long-standing belief, a recent contribution introduces an elastic probing technique based on fixed interval thresholds. Although this method presents improvements over traditional strategies, its dependence on static thresholds limits its theoretical optimality. In this paper, we propose a new conceptual model for optimizing hash table probing, inspired by human behavior in selecting restroom stalls - dubbed the "Bathroom Model." Unlike fixed or purely random approaches, our technique dynamically updates probing decisions using previously observed occupancy patterns, resulting in a more intelligent and adaptive search process. We rigorously formalize this model, analyze its theoretical properties, and benchmark its performance against leading hash table algorithms. Our findings indicate that adaptive probing mechanisms can significantly enhance search efficiency while keeping computational demands minimal. This work not only sheds new light on an extensively studied problem but also points to broader algorithmic opportunities in rethinking classical data structures.

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Qiantong Wang. 2025-02-16. The Bathroom Model: A Realistic Approach to Hash Table Algorithm Optimization. https://arxiv.org/abs/2502.10977

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