Which of the following sentences regarding Viable prefixes is/are CORRECT?
https://gatecse.in/viable-prefixes-and-handle-in-lr-parsing/
Answer is D.
I : Definition of viable prefix -
Viable prefixes are the prefixes of right sentential forms that do not extend beyond the end of its handle.
i.e. a viable prefix either has no handle or just one possible handle on the extreme RIGHT which can be reduced.
II : Definition of viable prefix -
viable prefixes are the set of prefixes of right sentential forms that can appear on the stack of a shiftreduce parser
III :The set of all viable prefixes of a context-free language is a REGULAR LANGUAGE. i.e., viable prefixes can be recognized by using a FINITE AUTOMATA.
So I, II & III are true.
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