Abstract
Efficient algorithms are given to find the maximum lengthn of an ordered list in which 4 elements can be merged using exactlyk comparisons. A top down algorithm for the (2,n) merge problem is discussed and is shown to obtain the optimal merge length first reported by Hwang and Lin. Our algorithms combine this top down approach and strong heuristics, some of which derived from Hwang's optimal algorithm for the (3,n) problem, and produce a lengthn which is close to the optimal lengthf 4(k).
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On leave at the Dept. of Mathematics and Dept. of Mechanical Engineering, University of California, Berkeley, California 94720.
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Alagar, V.S., Bui, T.D. & Thanh, M. Efficient algorithms for merging. BIT 23, 409–428 (1983). https://doi.org/10.1007/BF01933617
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DOI: https://doi.org/10.1007/BF01933617