Dynamic Symmetry Breaking Constraints
نویسندگان
چکیده
We present a general method for dynamically posting symmetry breaking constraints during search. The basic idea is very simple. Given any set of symmetry breaking constraints, if during search a symmetry of one of these constraints is entailed and this is consistent with previously posted symmetry breaking constraints, then we post this constraint. We illustrate the method with two examples where a polynomial number of symmetry breaking constraints break an exponential number of symmetries. Like existing static methods for symmetry breaking, this symmetry breaking method benefits from fast and effective constraint propagation. In addition, like existing dynamic methods for symmetry breaking, this symmetry breaking methods does not conflict with the branching heuristic. Initial experimental results appear promising.
منابع مشابه
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