Title
Building Strategies Into Qbf Proofs
Abstract
Strategy extraction is of great importance for quantified Boolean formulas (QBF), both in solving and proof complexity. So far in the QBF literature, strategy extraction has been algorithmically performed from proofs. Here we devise the first QBF system where (partial) strategies are built into the proof and are piecewise constructed by simple operations along with the derivation. This has several advantages: (1) lines of our calculus have a clear semantic meaning as they are accompanied by semantic objects; (2) partial strategies are represented succinctly (in contrast to some previous approaches); (3) our calculus has strategy extraction by design; and (4) the partial strategies allow new sound inference steps which are disallowed in previous central QBF calculi such as Q-Resolution and long-distance Q-Resolution. The last item (4) allows us to show an exponential separation between our new system and the previously studied reductionless long-distance resolution calculus. Our approach also naturally lifts to dependency QBFs (DQBF), where it yields the first sound and complete CDCL-style calculus for DQBF, thus opening future avenues into CDCL-based DQBF solving.
Year
DOI
Venue
2021
10.1007/s10817-020-09560-1
JOURNAL OF AUTOMATED REASONING
Keywords
DocType
Volume
QBF, DQBF, Resolution, Proof complexity
Journal
65
Issue
ISSN
Citations 
1
0168-7433
0
PageRank 
References 
Authors
0.34
0
3
Name
Order
Citations
PageRank
Olaf Beyersdorff122330.33
Joshua Blinkhorn236.16
Meena Mahajan368856.90