On Generators of Random Quasigroup Problems

  • Roman Barták
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3978)


Problems that can be sampled randomly are a good source of test suites for comparing quality of constraint satisfaction techniques. Quasigroup problems are representatives of structured random problems that are closer to real-life problems and hence more suitable for benchmarking. In this paper, we describe in detail generators for Quasigroup Completion Problem (QCP) and Quasigroups with Holes (QWH). In particular, we study an improvement of the generator for QCP that produces a larger number of satisfiable problems by using propagation through the all-different constraint. We also re-formulate the algorithm for generating QWH that is much faster than the original generator. Finally, we provide an experimental comparison of all presented generators.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Roman Barták
    • 1
  1. 1.Faculty of Mathematics and PhysicsCharles UniversityPragueCzech Republic

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