QRATPre+: Effective QBF Preprocessing via Strong Redundancy Properties

  • Florian LonsingEmail author
  • Uwe Egly
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11628)


We present version 2.0 of QRATPre+, a preprocessor for quantified Boolean formulas (QBFs) based on the \(\mathsf {QRAT} \) proof system and its generalization \(\mathsf {QRAT}^{+} \). These systems rely on strong redundancy properties of clauses and universal literals. QRATPre+ is the first implementation of these redundancy properties in \(\mathsf {QRAT} \) and \(\mathsf {QRAT}^{+} \) used to simplify QBFs in preprocessing. It is written in C and features an API for easy integration in other QBF tools. We present implementation details and report on experimental results demonstrating that QRATPre+ improves upon the power of state-of-the-art preprocessors and solvers.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Computer Science DepartmentStanford UniversityStanfordUSA
  2. 2.Institute of Logic and ComputationTU WienViennaAustria

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