Regularity Problems for Weak Pushdown ω-Automata and Games
نویسندگان
چکیده
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.
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