More Concise Representation of Regular Languages by Automata and Regular Expressions

  • Viliam Geffert
  • Carlo Mereghetti
  • Beatrice Palano
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5257)


We consider two formalisms for representing regular languages: constant height pushdown automata and straight line programs for regular expressions. We constructively prove that their sizes are polynomially related. Comparing them with the sizes of finite state automata and regular expressions, we obtain optimal exponential and double exponential gaps, i.e., a more concise representation of regular languages.


Pushdown automata regular expressions straight line programs descriptional complexity 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Viliam Geffert
    • 1
  • Carlo Mereghetti
    • 2
  • Beatrice Palano
    • 2
  1. 1.Department of Computer ScienceP. J. Šafárik UniversityKošiceSlovakia
  2. 2.Dipartimento di Scienze dell’InformazioneUniversità degli Studi di MilanoMilanoItaly

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