Symmetries in constraint satisfaction or combinatorial optimization problems can cause considerable dificulties for exact solvers. One way to overcome the problem is to employ sophisticated models with no or at least less symmetries. However, this often requires a lot of experience from the user who is carrying out the modeling. Moreover, some problems even contain inherent symmetries that cannot be broken by remodeling. We present an approach that detects symmetric choice points during the search. It enables the user to find solutions for complex problems with minimal effort spent on modeling.
Keywordssymmetry breaking during search graph partitioning n-queens problem golfer problem
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