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On NFA Reductions

  • Lucian Ilie
  • Gonzalo Navarro
  • Sheng Yu
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3113)

Abstract

We give faster algorithms for two methods of reducing the number of states in nondeterministic finite automata. The first uses equivalences and the second uses preorders. We develop restricted reduction algorithms that operate on position automata while preserving some of its properties. We show empirically that these reductions are effective in largely reducing the memory requirements of regular expression search algorithms, and compare the effectiveness of different reductions.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Lucian Ilie
    • 1
  • Gonzalo Navarro
    • 2
  • Sheng Yu
    • 1
  1. 1.Department of Computer ScienceUniversity of Western OntarioLondonCanada
  2. 2.Department of Computer ScienceUniversity of ChileSantiagoChile

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