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arXiv · 2603.05676

How to Sort in a Refrigerator: Simple Entropy-Sensitive Strictly In-Place Sorting Algorithms

Ofek Gila·Michael T. Goodrich·Vinesh Sridhar
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Abstract

While modern general-purpose computing systems have ample amounts of memory, it is still the case that embedded computer systems, such as in a refrigerator, are memory limited; hence, such embedded systems motivate the need for strictly in-place algorithms, which use only O(1) additional memory besides that used for the input. In this paper, we provide the first comparison-based sorting algorithms that are strictly in-place and have a running time that is optimal in terms of the run-based entropy, H(A), of an input array, A, of size n. In particular, we describe two remarkably simple paradigms for implementing stack-based natural mergesort algorithms to be strictly in-place in O(n(1 + H(A))) time.

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Ofek Gila, Michael T. Goodrich, Vinesh Sridhar. 2026-03-05. How to Sort in a Refrigerator: Simple Entropy-Sensitive Strictly In-Place Sorting Algorithms. https://arxiv.org/abs/2603.05676

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