English

MR-RePair: Grammar Compression based on Maximal Repeats

Data Structures and Algorithms 2019-02-19 v2

Abstract

We analyze the grammar generation algorithm of the RePair compression algorithm and show the relation between a grammar generated by RePair and maximal repeats. We reveal that RePair replaces step by step the most frequent pairs within the corresponding most frequent maximal repeats. Then, we design a novel variant of RePair, called MR-RePair, which substitutes the most frequent maximal repeats at once instead of substituting the most frequent pairs consecutively. We implemented MR-RePair and compared the size of the grammar generated by MR-RePair to that by RePair on several text corpus. Our experiments show that MR-RePair generates more compact grammars than RePair does, especially for highly repetitive texts.

Keywords

Cite

@article{arxiv.1811.04596,
  title  = {MR-RePair: Grammar Compression based on Maximal Repeats},
  author = {Isamu Furuya and Takuya Takagi and Yuto Nakashima and Shunsuke Inenaga and Hideo Bannai and Takuya Kida},
  journal= {arXiv preprint arXiv:1811.04596},
  year   = {2019}
}
R2 v1 2026-06-23T05:12:17.892Z