Deterministic Single - State 2 - Pdas Are Turing - Complete
نویسندگان
چکیده
The well-known simulation of Turing machines by push-down automata with two stacks is shown to be possible, even if the latter has only a single state and is deterministic. This sheds new light on the nature of states and their relationship with storage, and enables a unification of different types of abstract machines. Moreover, further refinements of the Chomsky hierarchy are proposed.
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