Two-Tier Relaxed Heaps

  • Amr Elmasry
  • Claus Jensen
  • Jyrki Katajainen
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4288)


We introduce an adaptation of run-relaxed heaps which provides efficient heap operations with respect to the number of element comparisons performed. Our data structure guarantees the worst-case cost of O(1) for findmin, insert, and decrease; and the worst-case cost of O(lg n) with at most lg n + 3 lg lg n + O(1) element comparisons for delete, improving the bound of \(3\lg n + O(1)\) on the number of element comparisons known for run-relaxed heaps. Here, n denotes the number of elements stored prior to the operation in question, and lg n equals max{1, log2 n}.


Active Node Minimum Element Priority Queue Lower Store Current Minimum 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Amr Elmasry
    • 1
  • Claus Jensen
    • 2
  • Jyrki Katajainen
    • 2
  1. 1.Department of Computer Engineering and SystemsAlexandria UniversityAlexandriaEgypt
  2. 2.Department of ComputingUniversity of CopenhagenCopenhagen EastDenmark

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