A case study in comparison based complexity: Finding the nearest value(s)

  • Walter Cunto
  • J. Ian Munro
  • Patricio V. Poblete
Session 1 Invited Presentation
Part of the Lecture Notes in Computer Science book series (LNCS, volume 519)


It is shown that 5n/4 plus-minus lower order terms comparisons on average are necessary and sufficient to solve the problem of finding the values of ranks immediately above and below a specified element x in a set X of size n>1. When x turns out to be the median of X, 1.5n+√πn/8+O(lg n) comparisons are proven to be sufficient. n+min(k, nk)+3 ln n+O(1) comparisons are sufficient if k, the rank of x in X, differs from n/2 by Θ(n).


Average Cost Close Neighbor Close Comparison Neighbor Problem Current Neighbor 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1991

Authors and Affiliations

  • Walter Cunto
    • 1
  • J. Ian Munro
    • 2
  • Patricio V. Poblete
    • 3
  1. 1.Centro Científico IBM de VenezuelaCaracasVenezuela
  2. 2.Department of Computer ScienceUniversity of WaterlooWaterlooCanada
  3. 3.Departamento de Ciencias de la ComputaciónUniversidad de ChileSantiagoChile

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