Local search algorithms for SAT: Worst-case analysis

  • Edward A. Hirsch
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1432)


Recent experiments demonstrated that local search algorithms (e.g. GSAT) axe able to find satisfying assignments for many “hard” Boolean formulas. However, no non-trivial worst-case upper bounds were proved, although many such bounds of the form 2itαn (α < 1 is a constant) are known for other SAT algorithms, e.g. resolution-like algorithms. In the present paper we prove such a bound for a local search algorithm, namely for CSAT. The class of formulas we consider covers most of DIMACS benchmarks, the satisfiability problem for this class of formulas is NP-complete.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Edward A. Hirsch
    • 1
  1. 1.Steklov Institute of Mathematics at St.PetersburgSt.PetersburgRussia

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