Solving a cutting-stock problem with the constraint logic programming language CHIP

CHIP is a new constraint logic programming language combining the declarative aspect of logic programming with the efficiency of constraint manipulation techniques. In the present paper, the authors show an application of CHIP to a two-dimensional cutting stock problem. This problem is highly combinatorial and is generally solved by specific programs written in procedural languages. The authors present two approaches to solve this problem in CHIP and compare them with the standard ones. It turns out that, although CHIP greatly simplifies the problem statement, it is comparable in efficiency to specialized programs. Of particular interest is the ability to use symbolic constraints to prune the search space.