Poketree: A Dynamically Competitive Data Structure with Good Worst-Case Performance

  • Jussi Kujala
  • Tapio Elomaa
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4288)


We introduce a new O(lg lg n)-competitive binary search tree data structure called poketree that has the advantage of attaining, under worst-case analysis, O(lg n) cost per operation, including updates. Previous O(lg lg n)-competitive binary search tree data structures have not achieved O(lg n) worst-case cost per operation. A standard data structure such as red-black tree or deterministic skip list can be augmented with the dynamic links of a poketree to make it O(lg lg n)-competitive. Our approach also uses less memory per node than previous competitive data structures supporting updates.


Competitive Ratio Binary Search Static Successor Static Link Reference 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 2006

Authors and Affiliations

  • Jussi Kujala
    • 1
  • Tapio Elomaa
    • 1
  1. 1.Institute of Software SystemsTampere University of TechnologyTampereFinland

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