Shadoks Approach to Minimum Partition into Plane Subgraphs (CG Challenge)

Authors Loïc Crombez , Guilherme D. da Fonseca , Yan Gerard , Aldo Gonzalez-Lorenzo

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Author Details

Loïc Crombez
  • LIMOS, Université Clermont Auvergne, Aubière, France
Guilherme D. da Fonseca
  • LIS, Aix-Marseille Université, France
Yan Gerard
  • LIMOS, Université Clermont Auvergne, Aubière, France
Aldo Gonzalez-Lorenzo
  • LIS, Aix-Marseille Université, France


We would like to thank Hélène Toussaint, Raphaël Amato, Boris Lonjon, and William Guyot-Lénat from LIMOS, as well as the Qarma and TALEP teams and Manuel Bertrand from LIS, who continue to make the computational resources of the LIMOS and LIS clusters available to our research. We would also like to thank the challenge organizers and other competitors for their time, feedback, and making this whole event possible.

Cite AsGet BibTex

Loïc Crombez, Guilherme D. da Fonseca, Yan Gerard, and Aldo Gonzalez-Lorenzo. Shadoks Approach to Minimum Partition into Plane Subgraphs (CG Challenge). In 38th International Symposium on Computational Geometry (SoCG 2022). Leibniz International Proceedings in Informatics (LIPIcs), Volume 224, pp. 71:1-71:8, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2022)


We explain the heuristics used by the Shadoks team to win first place in the CG:SHOP 2022 challenge that considers the minimum partition into plane subgraphs. The goal is to partition a set of segments into as few subsets as possible such that segments in the same subset do not cross each other. The challenge has given 225 instances containing between 2500 and 75000 segments. For every instance, our solution was the best among all 32 participating teams.

Subject Classification

ACM Subject Classification
  • Theory of computation → Computational geometry
  • Plane graphs
  • graph coloring
  • intersection graph
  • conflict optimizer
  • line segments
  • computational geometry


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