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Updates (Oct. 30 2023)


  • Combinatorial Reconfiguration is a novel algorithmic concept that provides mathematical models and analysis for "transformations over state spaces." Its appearance ranges from theory to applications. However, its technical achievements are hard to access. Thus, it is required to found a common infrastructure for utilizing and applying the algorithmic technology of combinatorial reconfiguration. See this website for more backgrounds.
  • The 2nd Combinatorial Reconfiguration Challenge (CoRe Challenge 2023) is a competition aiming for practically exploring the combinatorial reconfiguration.
  • This 2nd challenge targets the Independent Set Reconfiguration (ISR) problem.
  • The ISR problem is one of the most well-studied reconfiguration problems. Theoretically, the problem is PSPACE-complete, which implies that there exist instances such that even a shortest reconfiguration sequence requires a super polynomial steps. Theoretical results and their references can be found in a survey by N. Nishimura.


Date Event
Dec. 14, 2022 Challenge is open (you can join at any point)
Mar. 1st 2023 Registration is open
Apr. 30, 2023, 23:59 (AoE, UTC-12) Challenge ends (registration/submission deadline)



  • Takehiro Ito (Tohoku University, Japan)
  • Yoshio Okamoto (The University of Electro-Communications, Japan)
  • Takehide Soh (Kobe University, Japan)
  • Tomoya Tanjo (National Institute of Genetics, Japan)


KAKENHI Grant-in-Aid for Transformative Research Areas (B)
"Fusion of Computer Science, Engineering and Mathematics Approaches for Expanding Combinatorial Reconfiguration"

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