Skolem Functions for DQBF

  • Karina Wimmer
  • Ralf Wimmer
  • Christoph Scholl
  • Bernd Becker
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9938)

Abstract

We consider the problem of computing Skolem functions for satisfied dependency quantified Boolean formulas (DQBFs). We show how Skolem functions can be obtained from an elimination-based DQBF solver and how to take preprocessing steps into account. The size of the Skolem functions is optimized by don’t-care minimization using Craig interpolants and rewriting techniques. Experiments with our DQBF solver HQS show that we are able to effectively compute Skolem functions with very little overhead compared to the mere solution of the formula.

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Copyright information

© Springer International Publishing AG 2016

Authors and Affiliations

  • Karina Wimmer
    • 1
  • Ralf Wimmer
    • 1
    • 2
  • Christoph Scholl
    • 1
  • Bernd Becker
    • 1
  1. 1.Albert-Ludwigs-Universität FreiburgFreiburg im BreisgauGermany
  2. 2.Dependable Systems and SoftwareSaarland UniversitySaarbrückenGermany

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