Deleting Automata with a Restart Operation and Marcus Grammars
نویسندگان
چکیده
We introduce normal deleting automata with a restart operation (norm-DRA) and contextual grammars with regular selection (CGR). Both norm-DRA and CGR allow to describe syntax of (natural) languages as reduction systems. Some previously studied classes of contextual languages can be expressed using both norm-DRA and CGR. We give a hierarchy of some subclasses of norm-DRA and show the corresponding hierarchy of subclasses CGR. We also show that CGR-and norm-DRA-languages contain whole DCFL and are incomparable with CFL.
منابع مشابه
Deleting Automata with a Restart Operation
A special type of linear bounded automata, called deleting automata with a restart operation, are introduced, and their language recognition power is studied.
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