Resolution of Structured Sat Problems With

Many satissability problems called structured SAT problems (like Ramsey, PigeonHole, and so on) may be very shortly deened with Score(FD/B), a boolean constraint programming language design at the Computer Research Center of Dijon (CRID). In addition to the expressiveness, design features of the language (cardinality constraints) are also used to detect some properties (symmetries) of the problems at the compilation of the source program. The detected symmetries (if any) are used by the extended resolution method to prune eeciently the search space. In this paper, we present an original approach which exploits the symmetry properties, statically detected, to improve the systematic local search method supported by Score(FD/B). We also describe how to make use of these properties on the applications Ramsey and PigeonHole. Then we report some experimental results. The system Score(FD/B) has been developped in C on a SUN SPARC 10. 1 Score(FD/B) is the acronym of System of COnstraints and associated REpairs methods for solving Constraint Satisfaction Problems on Finite Domains (FD) restricted to Booleans (B).