A SAT-based Method for Solving the Two-dimensional Strip Packing Problem
نویسندگان
چکیده
We propose a satisfiability testing (SAT) based exact approach for solving the two-dimensional strip packing problem (2SPP). In this problem, we are given a set of rectangles and one large rectangle called a strip. The goal of the problem is to pack all rectangles without overlap, into the strip by minimizing the overall height of the packing. We show the method solves a 2SPP by translating it to SAT problems through a SAT encoding called order encoding. Generated SAT problems tend to be large, then we show techniques to reduce the search space by utilizing symmetries and relations of rectangles. To solve a 2SPP, that is, to compute the minimum height of a 2SPP, we need to repeatedly solve similar SAT problems. We then reuse learned clauses, assumptions, and models, which are obtained from previously solved SAT problems, to efficiently compute the minimum height. We attempt to solve 38 instances from the literature and obtain the total of 29 optimal solutions, including the solutions of two open problems.
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عنوان ژورنال:
- Fundam. Inform.
دوره 102 شماره
صفحات -
تاریخ انتشار 2010