Using the symmetry of relations to establish arc-consistency in constraint networks
نویسندگان
چکیده
In [1, 2], Bessière and Cordier said that the AC-6 arc-consistency algorithm is optimal in time on constraint networks where nothing is known about the constraint semantics. However, in constraint networks, it is always assumed that constraints are symmetric. None of the previous algorithms achieving arc-consistency (AC-3 [5, 6], AC-4 [7], AC-6) use this property. We propose here an improved version of AC-6 (the best algorithm for arcconsistency) which uses this property. Then, we claim that our new algorithm is optimal in the number of constraint checks performed.
منابع مشابه
A fast algorithm to establish arc-consistency in constraint networks
In [1], Bessière and Cordier said that the AC-6 arc-consistency algorithm is optimal in time on constraint networks where nothing is known about the constraint semantics. However, in constraint networks, it is always assumed that constraints are symmetric. None of the previous algorithms achieving arc-consistency (AC-3, AC-4, AC-6) use this property. We propose here an improved version of AC-6 ...
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