3 1 Ja n 20 06 Behavior of heuristics and state space structure near SAT / UNSAT transition
نویسنده
چکیده
We study the behavior of ASAT, a heuristic for solving satisfiability problems by stochastic local search near the SAT/UNSAT transition. The heuristic is focused, i.e. only variables in unsatisfied clauses are updated in each step, and is significantly simpler, while similar to, walksat or Focused Metropolis Search. We show that ASAT solves instances as large as N = 10 in linear time, on average, up to α = 4.21 for random 3SAT. For K higher than 3, ASAT appears to solve instances at the Montanari-Ricci-Tersenghi-Parisi “FRSB threshold” αs(K) in linear time, up to K = 7.
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