A Simple Fast Hybrid Pattern-Matching Algorithm

  • Frantisek Franek
  • Christopher G. Jennings
  • William F. Smyth
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3537)


The Knuth-Morris-Pratt (KMP) pattern-matching algorithm guarantees both independence from alphabet size and worst-case execution time linear in the pattern length; on the other hand, the Boyer-Moore (BM) algorithm provides near-optimal average-case and best-case behaviour, as well as executing very fast in practice. We describe a simple algorithm that employs the main ideas of KMP and BM (with a little help from Sunday) in an effort to combine these desirable features. Experiments indicate that in practice the new algorithm is among the fastest exact pattern-matching algorithms discovered to date, perhaps dominant for alphabet size 8 or more.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Frantisek Franek
    • 1
  • Christopher G. Jennings
    • 2
  • William F. Smyth
    • 1
    • 3
  1. 1.Algorithms Research Group, Department of Computing & SoftwareMcMaster UniversityHamiltonCanada
  2. 2.School of Computing ScienceSimon Fraser UniversityBurnabyCanada
  3. 3.School of ComputingCurtin UniversityPerthAustralia

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