Limitations of Non-Deterministic Finite Automata Imposed by One Letter Input Alphabet
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چکیده
NFA usually requires significantly less states than DFA to recognize the same language. NFAs in one letter input alphabet are more restricted and the gap between NFAs and DFAs decreases, because the power of NFA is in its ability to reach many subsets of its state set. We discuss limitations of DFAs in one letter input alphabet and show that approximately 1/4 of all subsets are unreachable and for every fixed k∈{2,...,number_of_states-2} at least one subset of size k is unreachable.
منابع مشابه
Limitations of Unary Finite Automata
NFA (Non-deterministic Finite Automata) usually require significantly less states than DFA (Deterministic Finite Automata) to recognize the same language. The power of NFA lies in its ability to be in many states simultaneously (i.e., in a subset of its state set). The usage of one letter input alphabet puts some restrictions on this ability of NFAs and decreases the gap between NFAs and DFAs. ...
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تاریخ انتشار 2005