Single-Solver Algorithms for 2QBF

(Poster Presentation)
  • Sam Bayless
  • Alan J. Hu
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7317)


2QBF is a restriction of QBF, in which at most one quantifier alternation is allowed. This simplifying assumption makes the problem easier to reason about, and allows for simpler unit propagation and clause/cube learning procedures.We introduce two new 2QBF algorithms that take advantage of 2QBF specifically. The first improves upon earlier work by Ranjan, Tang, and Malik (2004), while the second introduces a new ‘free’ decision heuristic that doesn’t need to respect quantifier order. Implementations of both new algorithms perform better than two state-of-the-art general QBF solvers on formal verification and AI planning instances.


Decision Variable Unit Propagation Decision Level Boolean Formula Boolean Modeling 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Sam Bayless
    • 1
  • Alan J. Hu
    • 1
  1. 1.University of British ColumbiaVancouverCanada

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