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arXiv · 2502.06461

New simple and fast quicksort algorithm for equal keys

Parviz Afereidoon
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Abstract

This paper introduces a novel and efficient partitioning technique for quicksort, specifically designed for real-world data with duplicate elements (50-year-old problem). The method is referred to as "equal quicksort" or "eqsort". Based on the experimental findings, it has been determined that the newly developed algorithm, eqsort, is competitive with the best current implementations,such as fat partitioning algorithms and dual-pivot quicksort. This method offers several advantages over the commonly used dual-pivot method and pdqsort partitioning, making it a potential replacement.

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Parviz Afereidoon. 2025-02-10. New simple and fast quicksort algorithm for equal keys. https://arxiv.org/abs/2502.06461

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