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Thresholds and Optimal Binary Comparison Search Trees

Extended Abstract
  • Richard Anderson
  • Sampath Kannan
  • Howard Karloff
  • Richard E. Ladner
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2245)

Abstract

We present an O(n 4)-time algorithm for the following problem: Given a set of items with known access frequencies, find the optimal binary search tree under the realistic assumption that each comparison can only result in a two-way decision: either an equality comparison or a less-than comparison. This improves the best known result of O(n 5) time, which is based on split tree algorithms. Our algorithm relies on establishing thresholds on the frequency of an item that can occur as an equality comparison at the root of an optimal tree.

Keywords

Side Branch Main Branch Maximum Probability Optimal Cost Binary Search Tree 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2001

Authors and Affiliations

  • Richard Anderson
    • 1
  • Sampath Kannan
    • 2
  • Howard Karloff
    • 3
    • 5
  • Richard E. Ladner
    • 4
  1. 1.Department of Computer Science and EngineeringUniversity of WashingtonSeattle
  2. 2.AT&T Labs-Research and Department of CISUniversity of PennsylvaniaPhiladelphia
  3. 3.AT&T Labs-ResearchFlorham Park
  4. 4.Department of Computer Science and EngineeringUniversity of WashingtonSeattle
  5. 5.College of Computing, Georgia Institute of TechnologyAtlanta

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