A linear extension x,x2xs ... of a partially ordered set (X, <) has a bump whenever xi < xi+l. We examine the problem of determining linear extensions with as few bumps as possible. Heuristic algorithms for approximate bump minimization are considered. AhfS (MOS) subject classifications (1980). Prim
Minimizing bumps in ordered sets by substitution decomposition
โ Scribed by George Steiner
- Publisher
- Elsevier Science
- Year
- 1989
- Tongue
- English
- Weight
- 495 KB
- Volume
- 76
- Category
- Article
- ISSN
- 0012-365X
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โฆ Synopsis
A linear extension x1x2. . . x, of a partially or&red set P has a bump whenever Xi <xi+1 in P. The bump number problem is to find a linear extension of P with the smallest possible number of bumps. We present a basic decomposition theorem for this problem. This leads to simple formulae for the bump number of series-parallel posets.
๐ SIMILAR VOLUMES
A simply polynomial time algorithm is given for computing the setup number, or jump number, of an ordered set with fixed width. This arises as an interesting application of a polynomial time algorithm for solving a more general weighted problem in precedence constrained scheduling.