Branch and Bound Algorithms to Solve Semiring Constraint Satisfaction Problems
نویسندگان
چکیده
The Semiring Constraint Satisfaction Problem (SCSP) framework is a popular approach for the representation of partial constraint satisfaction problems. Considerable research has been done in solving SCSPs, but limited work has been done in building general SCSP solvers. This paper is a part of a series of papers in which incremental changes are made to a branch and bound (BnB) algorithm in order to develop a truly e cient SCSP solver. In this spirit we present two variants of a BnB algorithm: a backjumping algorithm and a forward checking algorithm. These algorithms are based on the maximal constraints algorithms of Freuder and Wallace [3], and we show they perform better than the BnB algorithm on harder problems.
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Modeling and Solving Semiring Constraint Satisfaction Problems by Transformation to Weighted Semiring Max-SAT
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