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arXiv · 2012.08589

Sorting Lists with Equal Keys Using Mergesort in Linear Time

Albert Tedja
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Abstract

This article introduces a new optimization method to improve mergesort's runtime complexity, when sorting sequences that have equal keys to $O(n log_2 k)$, where $k$ is the number of distinct keys in the sequence. When $k$ is constant, it is evident that mergesort is capable of achieving linear time by utilizing linked lists as its underlying data structure. Mergesort linked list implementations can be optimized by introducing a new mechanism to group elements with equal keys together, thus allowing merge algorithm to achieve linear time.

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Albert Tedja. 2020-12-15. Sorting Lists with Equal Keys Using Mergesort in Linear Time. https://arxiv.org/abs/2012.08589

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