Around Hopcroft’s Algorithm

  • Manuel Baclet
  • Claire Pagetti
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4094)


In this paper, a reflection is made on an indeterminism inherent to Hopcroft’s minimization algorithm: the splitter choice. We have implemented two natural policies (FIFO and FILO) for managing the set of splitters for which we obtain the following practical results: the FILO strategy performs better than the FIFO strategy, in the case of a one letter alphabet, the practical complexity in the FILO case never exceeds a linear one and our implementation is more efficient than the minimization algorithm of the FSM tool. This implementation is being integrated in a finite automata library, the Dash library. Thus, we present an efficient manner to manipulate automata by using canonical minimal automata.


Finite automata minimization Hopcroft’s algorithm 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Manuel Baclet
    • 1
  • Claire Pagetti
    • 2
  1. 1.IRIT – UPS & CNRSLSV – ENS de Cachan & CNRS – Cachan, FranceToulouseFrance
  2. 2.ONERA / CertToulouseFrance

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