BIT Numerical Mathematics

, Volume 23, Issue 4, pp 409–428 | Cite as

Efficient algorithms for merging

  • V. S. Alagar
  • T. D. Bui
  • Mai Thanh
Part I Computer Science


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 lengthf4(k).


Optimal merging top down approach heuristic approach 


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Copyright information

© BIT Foundations 1983

Authors and Affiliations

  • V. S. Alagar
    • 1
  • T. D. Bui
    • 1
  • Mai Thanh
    • 1
  1. 1.Department of Computer ScienceConcordia UniversityMontrealCanada

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