On the Weak Prefix-Search Problem

  • Paolo Ferragina
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6661)


The weak-prefix search problem asks for the strings in a dictionary \({\cal S}\) that are prefixed by a pattern P[1,p], if any, otherwise it admits any answer. Strings in \({\cal S}\) have average length ℓ, are n in number, and are given in advance to be preprocessed, whereas pattern P is provided on-line. In this paper we solve this problem in the cache-oblivious model by using the optimal O(n logℓ) bits of space and O(p/B + log B n) I/Os. The searching algorithm is of Monte-Carlo type, so its answer is correct with high probability. We also extend our algorithmic scheme to the case in which a probability distribution over the queried prefixes is known, and eventually address the deterministic case too.


Internal Node Search Problem Tree Traversal Space Occupancy Blind Search 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Paolo Ferragina
    • 1
  1. 1.Dipartimento di InformaticaUniversità di PisaItaly

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