In Pursuit of the Dynamic Optimality Conjecture

  • John Iacono
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8066)


In 1985, Sleator and Tarjan introduced the splay tree, a self-adjusting binary search tree algorithm. Splay trees were conjectured to perform within a constant factor as any offline rotation-based search tree algorithm on every sufficiently long sequence—any binary search tree algorithm that has this property is said to be dynamically optimal. However, currently neither splay trees nor any other tree algorithm is known to be dynamically optimal. Here we survey the progress that has been made in the almost thirty years since the conjecture was first formulated, and present a binary search tree algorithm that is dynamically optimal if any binary search tree algorithm is dynamically optimal.


Online Algorithm Search Sequence Search Path Binary Search Tree Prefer Path 
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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© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • John Iacono
    • 1
  1. 1.Polytechnic Institute of New York UniversityBrooklynUSA

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