Improvements to propositional satisfiability search algorithms
Improvements to propositional satisfiability search algorithms
A Comparison between SAT and CSP Techniques
Constraints
AAAI'05 Proceedings of the 20th national conference on Artificial intelligence - Volume 1
Compiling Bayesian networks with local structure
IJCAI'05 Proceedings of the 19th international joint conference on Artificial intelligence
Decomposing global grammar constraints
CP'07 Proceedings of the 13th international conference on Principles and practice of constraint programming
CP'06 Proceedings of the 12th international conference on Principles and Practice of Constraint Programming
Revisiting the sequence constraint
CP'06 Proceedings of the 12th international conference on Principles and Practice of Constraint Programming
Reformulating Global Grammar Constraints
CPAIOR '09 Proceedings of the 6th International Conference on Integration of AI and OR Techniques in Constraint Programming for Combinatorial Optimization Problems
New Encodings of Pseudo-Boolean Constraints into CNF
SAT '09 Proceedings of the 12th International Conference on Theory and Applications of Satisfiability Testing
Decompositions of grammar constraints
AAAI'08 Proceedings of the 23rd national conference on Artificial intelligence - Volume 3
Circuit complexity and decompositions of global constraints
IJCAI'09 Proceedings of the 21st international jont conference on Artifical intelligence
SAT Encoding and CSP Reduction for Interconnected Alldiff Constraints
MICAI '09 Proceedings of the 8th Mexican International Conference on Artificial Intelligence
Lazy clause generation reengineered
CP'09 Proceedings of the 15th international conference on Principles and practice of constraint programming
Local consistency and SAT-solvers
CP'10 Proceedings of the 16th international conference on Principles and practice of constraint programming
Knowledge compilation with empowerment
SOFSEM'12 Proceedings of the 38th international conference on Current Trends in Theory and Practice of Computer Science
ILP'11 Proceedings of the 21st international conference on Inductive Logic Programming
Local consistency and SAT-solvers
Journal of Artificial Intelligence Research
Complexity issues related to propagation completeness
Artificial Intelligence
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In this paper we argue that an attractive and potentially very general way of achieving generalized arc consistency (GAC) on a constraint is by using unit propagation (UP) over a CNF encoding of the constraint. This approach to GAC offers a number of advantages over traditional constraint specific algorithms (propagators): it is easier to implement, it automatically provides incrementality and decrementality in a backtracking context, and it can provide clausal reasons to support learning and non-chronological backtracking. Although UP on standard CNF encodings of a constraint fails to achieve GAC, we show here that alternate CNF encodings can be used on which UP does achieve GAC. We provide a generic encoding applicable to any constraint. We also give structure specific encodings for the regular, among, and gen-sequence constraints on which UP can achieve GAC with the same run time bounds as previously presented propagators. Finally, we explain how a UP engine can be added to a CSP solver to achieve a seamless integration of constraints encoded in CNF and propagated via UP and those propagated via traditional constraint specific propagators.