On the power of nondeterminism in small two-way finite automata
Author(s)
Kapoutsis, Christos, 1974-
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Alternative title
On the power of nondeterminism in small 2DFA
Other Contributors
Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science.
Advisor
Michael Sipser.
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We examine the conjecture that one-way nondeterministic finite automata (NFAS) can be exponentially more succinct than two-way deterministic ones (2DFAS); equivalently, that no polynomial-size sequence of 2DFAs can recognize B, for B a particular sequence of regular languages that is among the hardest of those recognizable by polynomial-size sequences of 1NFAs. We prove that the most natural single-pass 2DFA algorithm for deciding B fails, "single-pass" meaning that the automaton is bound to terminate as soon as it reaches an endmarker for the first time. On the way, we introduce the notion of dilemmas as an interesting general tool for constructing hard inputs for 2DFAS.
Description
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004. Includes bibliographical references (p. 25-26).
Date issued
2004Department
Massachusetts Institute of Technology. Department of Electrical Engineering and Computer SciencePublisher
Massachusetts Institute of Technology
Keywords
Electrical Engineering and Computer Science.