Forward Injective Finite Automata: Exact and Random Generation of Nonisomorphic NFAs

  • Miguel Ferreira
  • Nelma MoreiraEmail author
  • Rogério Reis
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10952)


We define the class of forward injective finite automata (FIFA) and study some of their properties. Each FIFA has a unique canonical representation up to isomorphism. Using this representation an enumeration is given and an efficient uniform random generator is presented. We provide a conversion algorithm from a nondeterministic finite automaton or regular expression into an equivalent FIFA. Finally, we present some experimental results comparing the size of FIFA with other automata.


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Copyright information

© IFIP International Federation for Information Processing 2018

Authors and Affiliations

  1. 1.CMUP and DCCFaculdade de Ciências da Universidade do PortoPortoPortugal

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