Abstract
Nowadays many real problems can be modelled as Constraint Satisfaction Problems (CSPs) and solved using constraint programming techniques. In many situations, it is desirable to be ab le to state both hard constraints and soft constraints. Hard constraints must hold while soft constraints may be violated but as many as possible should be satisfied. Although the problem constraints can be divided into two groups, the order in which these constraints are studied can improve efficiency, particularly in problems with non-binary constraints. In this paper, we present a heuristic technique called Hard and Soft Constraint Ordering Heuristic (HASCOH) that carries out a classification of hard and soft constraints in order to study the tightest hard constraints first and to obtain ever better solutions. In this way, inconsistencies can be found earlier and the number of constraint checks can be significantly reduced.
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Salido, M.A., Barber, F. (2004). How to Classify Hard and Soft Constraints in Non-binary Constraint Satisfaction Problems. In: Coenen, F., Preece, A., Macintosh, A. (eds) Research and Development in Intelligent Systems XX. SGAI 2003. Springer, London. https://doi.org/10.1007/978-0-85729-412-8_16
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DOI: https://doi.org/10.1007/978-0-85729-412-8_16
Publisher Name: Springer, London
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