An Exponential Gap Between LasVegas and Deterministic Sweeping Finite Automata
نویسندگان
چکیده
A two-way finite automaton is sweeping if its input head can change direction only on the end-markers. For each n ≥ 2, we exhibit a problem that can be solved by a O(n)-state sweeping LasVegas automaton, but needs 2 states on every sweeping deterministic automaton.
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