Polynomial restrictions of SAT: What can be done with an efficient implementation of the Davis and Putnam's procedure?

  • Antoine Rauzy
Operation Research
Part of the Lecture Notes in Computer Science book series (LNCS, volume 976)


Constraint Solving Problems are NP-Complete and thus computationaly intractable. Two approaches have been used to tackle this intractability: the improvement of general purpose solvers and the research of polynomial time restrictions. An interesting question follows: what is the behavior of the former solvers on the latter restrictions?

In this paper, we examplify this problem by studying both theoretical and practical complexities of the Davis and Putnam's procedure on the two main polynomial restrictions of SAT, namely Horn-SAT and 2-SAT. We propose an efficient implementation and an improvement that make it quadratic in the worst case on these sub-classes. We show that this complexity is never reached in practice where linear times are observed, making the Davis and Putnam's as efficient as specialized algorithms.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • Antoine Rauzy
    • 1
  1. 1.LaBRI-CNRS URA 1304Université Bordeaux ITalenceFrance

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