Tractable Symmetry Breaking Using Restricted Search Trees
نویسندگان
چکیده
We present a new conceptual abstraction in symmetry breaking – the GE-tree. The construction and traversal of a GE-tree breaks all symmetries in any constraint satisfaction or similar problem. We give a polynomial-time algorithm for this construction in the case of CSPs with arbitrary value symmetries. We have implemented this technique, and supply experimental evidence of its practical effectiveness.
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