Optimal State Reductions of Automata with Partially Specified Behaviors

  • Nelma Moreira
  • Giovanni Pighizzini
  • Rogério Reis
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8939)


Nondeterministic finite automata with don’t care states, [4] namely states which neither accept nor reject, are considered. A cha- racterization of deterministic automata compatible with such a device is obtained. Furthermore, an optimal state bound for the smallest compatible deterministic automata is provided. Finally, it is proved that the problem of minimizing nondeterministic and deterministic don’t care automata is NP-complete.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Nelma Moreira
    • 1
  • Giovanni Pighizzini
    • 2
  • Rogério Reis
    • 1
  1. 1.Centro de Matemática e Faculdade de Ciências daUniversidade do PortoPortugal
  2. 2.Dipartimento di InformaticaUniversità degli Studi di MilanoItaly

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