摘要

We consider the problem of packing rectangles into bins that are unit squares, where the goal is to minimize the number of bins used. All rectangles have to be packed non-overlapping and orthogonal, i. e., axis-parallel. We present an algorithm with an absolute worst-case ratio of 2 for the case where the rectangles can be rotated by 90 degrees. This is optimal provided P not equal NP. For the case where rotation is not allowed, we prove an approximation ratio of 3 for the algorithm HYBRID FIRST FIT which was introduced by Chung et al. (SIAM J. Algebr. DiscreteMethods 3(1): 6676, 1982) and whose running time is slightly better than the running time of Zhang's previously known 3-approximation algorithm (Zhang in Oper. Res. Lett. 33(2): 121-126, 2005).

  • 出版日期2012-2