English

Circle graphs can be recognized in linear time

Data Structures and Algorithms 2026-01-01 v2 Discrete Mathematics

Abstract

To date, the best circle graph recognition algorithm runs in almost linear time as it relies on a split decomposition algorithm that uses the union-find data-structure. We show that in the case of circle graphs, the PC-tree data-structure allows one to avoid the union-find data-structure to compute the split decomposition in linear time. As a consequence, we obtain the first linear-time recognition algorithm for circle graphs.

Keywords

Cite

@article{arxiv.2512.23492,
  title  = {Circle graphs can be recognized in linear time},
  author = {Christophe Paul and Ignaz Rutter},
  journal= {arXiv preprint arXiv:2512.23492},
  year   = {2026}
}

Comments

To appear in 43rd International Symposium on Theoretical Aspects of Computer Science (STACS 2026)

R2 v1 2026-07-01T08:44:24.534Z