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Fooling a two-way nondeterministic multihead automaton with reversal number restriction

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Summary

We define a language L and show that it can be recognized by no two-way nondeterministic sensing multihead finite automaton with n a reversal bound, where n is the length of input words, and 1/3>a>0 is a real number. Since L is recognized by a two-way deterministic two-head finite automaton working in linear time we obtain, for two-way finite automata, that time, reading heads, and nondeterminism as resources cannot compensate for the reversal number restriction.

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Authors and Affiliations

  1. Department of Theoretical Cybernetics, Comenius University, CS-84215, Bratislava, Czechoslovakia

    J. Hromkovič

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  1. J. Hromkovič
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This work was supported as a part of the SPZV I-1-5/8 grant

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Hromkovič, J. Fooling a two-way nondeterministic multihead automaton with reversal number restriction. Acta Informatica 22, 589–594 (1985). https://doi.org/10.1007/BF00267046

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  • DOI: https://doi.org/10.1007/BF00267046

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