Looking for MUM and DAD: Text-text comparisons do help

  • Mike Paterson
  • Shlomit Tassa
  • Uri Zwick
Invited Talk
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1026)


It is known that about 4n/3 comparisons are needed, in the worst case, to find all the occurrences of the string aba in a text of length n if only pattern-text comparisons are allowed. We show that if text-text comparisons can be used then only about 5n/4 comparisons are required. This gives the first example in which text-text comparisons provably help.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • Mike Paterson
    • 1
  • Shlomit Tassa
    • 2
  • Uri Zwick
    • 2
  1. 1.Department of Computer ScienceUniversity of WarwickUK
  2. 2.Department of Computer ScienceTel Aviv UniversityIsrael

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