Automatically Generating and Solving Eternity II Style Puzzles

  • Geoff Harris
  • Bruce James Vanstone
  • Adrian GeppEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10868)


The Eternity II puzzle is an NP-complete problem. Prior researchers have generated data sets that are similar to the Eternity II problem. These data sets can be created in linear time, but this comes at the cost of easing the problem by introducing exploitable statistical features. The first contribution of this paper is a new method to generate data sets that are truly of Eternity II style. The second contribution is an Eternity II specific implementation of a constraint-satisfaction-problem style algorithm. Unlike most other published algorithms, this one has no form of look-ahead, filtering, forward checking, back jumping or k-consistency checks. Instead, it uses knowledge about the structure of the puzzle and the uniform distribution of edge colours. This approach is up to three orders of magnitude faster than previously published attempts.


Eternity II Edge Matching Puzzle Constraint satisfaction problem NP-complete 


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Bond Business SchoolBond UniversityGold CoastAustralia

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