Deterministic Algorithms for k-SAT Based on Covering Codes and Local Search

  • Evgeny Dantsin
  • Andreas Goerdt
  • Edward A. Hirsch
  • Uwe Schöning
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1853)

Abstract

We show that satisfiability of formulas in k-CNF can be decided deterministically in time close to (2k/(k + 1))n, where n is the number of variables in the input formula. This is the best known worst-case upper bound for deterministic k-SAT algorithms. Our algorithm can be viewed as a derandomized version of Schöning’s probabilistic algorithm presented in [15]. The key point of our algorithm is the use of covering codes together with local search. Compared to other “weakly exponential” algorithms, our algorithm is technically quite simple. We also show how to improve the bound above by moderate technical effort. For 3-SAT the improved bound is 1.481n.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • Evgeny Dantsin
    • 1
  • Andreas Goerdt
    • 2
  • Edward A. Hirsch
    • 3
  • Uwe Schöning
    • 4
  1. 1.Steklov Institute of MathematicsSt.PetersburgRussia
  2. 2.Fakultät für InformatikTU ChemnitzChemnitzGermany
  3. 3.Steklov Institute of MathematicsSt.PetersburgRussia
  4. 4.Abteilung Theoretische InformatikUniversität UlmUlmGermany

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