PSPACE-complete two-color planar placement games

  • Kyle Burke
  • Robert A. HearnEmail author
Original Paper


We show that the classic placement games Col and Snort are PSPACE-complete, resolving an open question of Schaefer (1978). We then show the related placement games Fjords and NoGo PSPACE-complete on planar graphs. All but NoGo are shown hard by reductions from Bounded 2-Player Constraint Logic; we then reduce Col to NoGo. The only previous complexity results for these games were that Col and Snort played on general graphs are PSPACE-complete, and NoGo is NP-hard on general graphs.


Complexity PSPACE Combinatorial game 


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Plymouth State UniversityPlymouthUSA
  2. 2.Portola ValleyUSA

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