When Simulation Meets Antichains

(On Checking Language Inclusion of Nondeterministic Finite (Tree) Automata)
  • Parosh Aziz Abdulla
  • Yu-Fang Chen
  • Lukáš Holík
  • Richard Mayr
  • Tomáš Vojnar
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6015)


We describe a new and more efficient algorithm for checking universality and language inclusion on nondeterministic finite word automata (NFA) and tree automata (TA). To the best of our knowledge, the antichain-based approach proposed by De Wulf et al. was the most efficient one so far. Our idea is to exploit a simulation relation on the states of finite automata to accelerate the antichain-based algorithms. Normally, a simulation relation can be obtained fairly efficiently, and it can help the antichain-based approach to prune out a large portion of unnecessary search paths. We evaluate the performance of our new method on NFA/TA obtained from random regular expressions and from the intermediate steps of regular model checking. The results show that our approach significantly outperforms the previous antichain-based approach in most of the experiments.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Parosh Aziz Abdulla
    • 1
  • Yu-Fang Chen
    • 1
  • Lukáš Holík
    • 2
  • Richard Mayr
    • 3
  • Tomáš Vojnar
    • 2
  1. 1.Uppsala University 
  2. 2.Brno University of Technology 
  3. 3.University of Edinburgh 

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