Filtering Algorithms for the NValue Constraint
نویسندگان
چکیده
منابع مشابه
The Increasing Nvalue Constraint
This paper introduces the Increasing Nvalue constraint, which restricts the number of distinct values assigned to a sequence of variables so that each variable in the sequence is less than or equal to its successor. This constraint is a specialization of the Nvalue constraint, motivated by symmetry breaking. Propagating the Nvalue constraint is known as an NP-hard problem. However, we show that...
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This reportdeals with global constraints for which the set of solutions can be recognized by an extended finite automaton whose size is bounded by a polynomial in , where is the number of variables of the corresponding global constraint. By reformulating the automaton as a conjunction of signature and transition constraints we show how to systematically obtain a filtering algorithm. Under some ...
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ژورنال
عنوان ژورنال: Constraints
سال: 2006
ISSN: 1383-7133,1572-9354
DOI: 10.1007/s10601-006-9001-9