ALGORITHMES POUR LA BIO-INFORMATIQUE ET
LA VISUALISATION
COURS 2
Raluca Uricaru
Chapter 32 of Introduction to Algorithms
Second Edition
by
Cormen, Leiserson, Rivest & Stein
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Naive string matcher
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Exercice
Suppose that all characters in the pattern P are different.
How do you accelerate the Naive string matcher to run in
time O(n) on an n-character text T?
Rabin – Karp matcher
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Exercices
1.  Working modulo q = 11, how many spurious hits does
the Rabin-Karp matcher encounter in text
T = 3141592653589793 ?
2.  How would you extend the Rabin-Karp method to the
problem of searching a text string for the occurrences
of the patterns in a given set of k patterns?
Knuth-Morris-Pratt (KMP) matcher
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Exercice
Compute the prefix function for the pattern
ababbabbabbababbabb
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