Nondeterminism Is Essential in Small 2FAs with Few Reversals
نویسنده
چکیده
On every n-long input, every two-way finite automaton (fa) can reverse its head O(n) times before halting. A fawith few reversals is an automaton where this number is only o(n). For every h, we exhibit a language that requires Ω(2) states on every deterministic fa with few reversals, but only h states on a nondeterministic fa with few reversals.
منابع مشابه
Nondeterminism is essential in small two-way finite automata with few reversals
On every n-long input, every two-way finite automaton (fa) can reverse its input head O(n) times before halting. A fawith few reversals is an automaton where this number is only o(n). For every h, we exhibit a language that can be recognized by an h-state nondeterministic fa with few reversals, but requires Ω(2) states on every deterministic fa with few reversals.
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On every n-long input, every two-way finite automaton (fa) can reverse its head O(n) times before halting. A fawith few reversals is an automaton where this number is only o(n). For every h, we exhibit a language that requires Ω(2) states on every deterministic fa with few reversals, but only h states on a nondeterministic fa with few reversals.
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