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An In-Place Sorting with O(n log n) Comparisons and O(n) Moves

Gianni Franceschini·Viliam Geffert
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Abstract

We present the first in-place algorithm for sorting an array of size n that performs, in the worst case, at most O(n log n) element comparisons and O(n) element transports. This solves a long-standing open problem, stated explicitly, e.g., in [J.I. Munro and V. Raman, Sorting with minimum data movement, J. Algorithms, 13, 374-93, 1992], of whether there exists a sorting algorithm that matches the asymptotic lower bounds on all computational resources simultaneously.

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Gianni Franceschini, Viliam Geffert. 2003-05-09. An In-Place Sorting with O(n log n) Comparisons and O(n) Moves. https://arxiv.org/abs/cs/0305005

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