We study the problem of cutting a number of pieces of the same length from n rolls of different lengths so that the remaining part of each utilized roll is either sufficiently short or sufficiently long. A piece is sufficiently short, if it is shorter than a pre-specified threshold value δ_(min), so that it can be thrown away as it cannot be used again for cutting future orders. And a piece is sufficiently long, if it is longer than a pre-specified threshold value δ_(max) (with δ_(max) > δ_(min)), so that it can reasonably be expected to be usable for cutting future orders of almost any length. We show that this problem, faced by a curtaining wholesaler, is solvable in O(n log n) time by analyzing a non-trivial class of allocation problems.
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