Regularity Problems for Weak Pushdown ω-Automata and Games

  • Christof Löding
  • Stefan Repke
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7464)


We show that the regularity and equivalence problems are decidable for deterministic weak pushdown ω-automata, giving a partial answer to a question raised by Cohen and Gold in 1978. We prove the decidability by a reduction to the corresponding problems for deterministic pushdown automata on finite words. Furthermore, we consider the problem of deciding for pushdown games whether a winning strategy exists that can be implemented by a finite automaton. We show that this problem is already undecidable for games defined by one-counter automata or visibly pushdown automata with a safety condition.


Normal Form Model Check State Strategy Regular Language Winning Strategy 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Christof Löding
    • 1
  • Stefan Repke
    • 1
  1. 1.Lehrstuhl für Informatik 7RWTH AachenGermany

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