Section: New Results

Symmetry Detection and Breaking in Constraint Satisfaction Problems

Participants : François Fages, Valentin Gatien-Baron.

In [33] , a novel symmetry detection procedure is introduced for detecting symmetries not only in instanciated constraint satisfaction problems but in parametric constraint satisfaction programs or models. The method proceeds by normalization of expressions with a term rewriting system. The evaluation of the method on classical benchmark problems, expressed in the OPL modeling language, shows that the interesting symmetries that are easy to break with constraints are detected in a few seconds, or minutes for the generalized perfect square problem.