English

Nearly-Optimal Mergesorts: Fast, Practical Sorting Methods That Optimally Adapt to Existing Runs

Data Structures and Algorithms 2019-05-07 v1

Abstract

We present two stable mergesort variants, "peeksort" and "powersort", that exploit existing runs and find nearly-optimal merging orders with practically negligible overhead. Previous methods either require substantial effort for determining the merging order (Takaoka 2009; Barbay & Navarro 2013) or do not have a constant-factor optimal worst-case guarantee (Peters 2001; Auger, Nicaud & Pivoteau 2015; Buss & Knop 2018). We demonstrate that our methods are competitive in terms of running time with state-of-the-art implementations of stable sorting methods.

Keywords

Cite

@article{arxiv.1805.04154,
  title  = {Nearly-Optimal Mergesorts: Fast, Practical Sorting Methods That Optimally Adapt to Existing Runs},
  author = {J. Ian Munro and Sebastian Wild},
  journal= {arXiv preprint arXiv:1805.04154},
  year   = {2019}
}
R2 v1 2026-06-23T01:51:27.817Z