Effective Preprocessing in SAT Through Variable and Clause Elimination

نویسندگان

  • Niklas Eén
  • Armin Biere
چکیده

Preprocessing SAT instances can reduce their size considerably. We combine variable elimination with subsumption and selfsubsuming resolution, and show that these techniques not only shrink the formula further than previous preprocessing efforts based on variable elimination, but also decrease runtime of SAT solvers substantially for typical industrial SAT problems. We discuss critical implementation details that make the reduction procedure fast enough to be practical.

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تاریخ انتشار 2005