Classifying the Complexity of Constraints Using Finite Algebras

@article{Bulatov2005ClassifyingTC,
  title={Classifying the Complexity of Constraints Using Finite Algebras},
  author={Andrei A. Bulatov and Peter Jeavons and Andrei A. Krokhin},
  journal={SIAM J. Comput.},
  year={2005},
  volume={34},
  pages={720-742}
}
Many natural combinatorial problems can be expressed as constraint satisfaction problems. This class of problems is known to be NP-complete in general, but certain restrictions on the form of the constraints can ensure tractability. Here we show that any set of relations used to specify the allowed forms of constraints can be associated with a finite universal algebra and we explore how the computational complexity of the corresponding constraint satisfaction problem is connected to the… 

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