The complexity of implicit and space efficient priority queues

  • Authors:
  • Christian W. Mortensen;Seth Pettie

  • Affiliations:
  • IT University of Copenhagen;Max Planck Institut für Informatik

  • Venue:
  • WADS'05 Proceedings of the 9th international conference on Algorithms and Data Structures
  • Year:
  • 2005

Quantified Score

Hi-index 0.01

Visualization

Abstract

In this paper we study the time-space complexity of implicit priority queues supporting the decreasekey operation. Our first result is that by using one extra word of storage it is possible to match the performance of Fibonacci heaps: constant amortized time for insert and decreasekey and logarithmic time for deletemin. Our second result is a lower bound showing that that one extra word really is necessary. We reduce the decreasekey operation to a cell-probe type game called the Usher's Problem, where one must maintain a simple data structure without the aid of any auxiliary storage.