An algebraic characterization of tractable constraints

  • Peter Jeavons
  • David Cohen
Session 11A: Scheduling
Part of the Lecture Notes in Computer Science book series (LNCS, volume 959)


Many combinatorial search problems may be expressed as ‘constraint satisfaction problems’, and this class of problems is known to be NP-complete. In this paper we investigate what restrictions must be imposed on the allowed constraints in order to ensure tractability. We describe a simple algebraic closure condition, and show that this is both necessary and sufficient to ensure tractability in Boolean valued problems. We also demonstrate that this condition is necessary for problems with arbitrary finite domains.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • Peter Jeavons
    • 1
  • David Cohen
    • 1
  1. 1.Department of Computer Science, Royal HollowayUniversity of LondonUK

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