A Constant Time Optimal Parallel Algorithm for Two-Dimensional Pattern Matching

  • Authors:
  • Maxime Crochemore;Leszek Gasieniec;Ramesh Hariharan;S. Muthukrishnan;Wojciech Rytter

  • Affiliations:
  • -;-;-;-;-

  • Venue:
  • SIAM Journal on Computing
  • Year:
  • 1998

Quantified Score

Hi-index 0.00

Visualization

Abstract

We give an alphabet-independent deterministic parallel algorithm for finding all occurrences of a pattern array of size mh x mw in a text array of size nh x nw in the concurrent-read-concurrent-write--parallel-random-access-machine (CRCW--PRAM) model. Our algorithm runs in O(1) time performing optimal, that is, O(nh x nw) work, following preprocessing of the pattern. This improves the previous best bound of O(log log m ) time with optimal work [A. Amir, G. Benson, and M. Farach, Proceedings 5th Annual ACM Symposium on Parallel Algorithms and Architectures, ACM, New York, 1993, pp. 79--85], following preprocessing of the pattern, where m=max{mh, mw}.The preprocessing required by our algorithm (and that due to Amir, Benson, and Farach) can be accomplished in O(log log m) time and O(mh x mw) work [M. Crochemore et al., manuscript, 1993], [R. Cole et al., manuscript, 1993].