Abstract
The notion of Boyer-Moore automaton was introduced by Knuth, Morris, and Pratt in their historical paper on fast pattern matching. It leads to an algorithm that requires more preprocessing but is more efficient than the original Boyer-Moore's algorithm. We formalize the notion of Boyer-Moore automaton and we give an efficient building algorithm. Also, bounds on the number of states are presented, and the concept of potential of a transition is introduced to improve the worst-and average-case behavior of these machines. We show that looking at the rightmost unknown character, as suggested by Knuthet al., is not necessarily optimal.
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Communicated by Alberto Apostolico.
R. A. Baeza-Yates gratefully acknowledges the support of Grant C-11001 from Fundación Andes, and C. Choffrut gratefully acknowledges the support of the PRC Mathématiques et Informatique.
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Baeza-Yates, R.A., Choffrut, C. & Gonnet, G.H. On Boyer-Moore automata. Algorithmica 12, 268–292 (1994). https://doi.org/10.1007/BF01185428
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DOI: https://doi.org/10.1007/BF01185428