Maintaining arc consistency algorithms during the search with an optimal time and space complexity
نویسنده
چکیده
In this paper, we present in detail the versions of the arc consistency algorithms for binary constraints based on list of supports and last value when they are maintained during the search for solutions. In other words, we give the explicit codes of MAC-6 and MAC-7 algorithms. Moreover, we present an original way to restore the last values of AC-6 and AC-7 algorithms in order to obtain a MAC version of these algorithms whose space complexity remains in O(ed) while keeping the O(ed) time complexity on any branch of the tree search. This result outperforms all previous studies.
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