English

A Structural Linear-Time Algorithm for Computing the Tutte Decomposition

Data Structures and Algorithms 2025-08-11 v1 Discrete Mathematics Combinatorics

Abstract

The block-cut tree decomposes a connected graph along its cutvertices, displaying its 2-connected components. The Tutte-decomposition extends this idea to 2-separators in 2-connected graphs, yielding a canonical tree-decomposition that decomposes the graph into its triconnected components. In 1973, Hopcroft and Tarjan introduced a linear-time algorithm to compute the Tutte-decomposition. Cunningham and Edmonds later established a structural characterization of the Tutte-decomposition via totally-nested 2-separations. We present a conceptually simple algorithm based on this characterization, which computes the Tutte-decomposition in linear time. Our algorithm first computes all totally-nested 2-separations and then builds the Tutte-decomposition from them. Along the way, we derive new structural results on the structure of totally-nested 2-separations in 2-connected graphs using a novel notion of stability, which may be of independent interest.

Keywords

Cite

@article{arxiv.2508.06212,
  title  = {A Structural Linear-Time Algorithm for Computing the Tutte Decomposition},
  author = {Romain Bourneuf and Tim Planken},
  journal= {arXiv preprint arXiv:2508.06212},
  year   = {2025}
}

Comments

41 pages, 4 figures