The Set of Minimal Words of a Context-Free Language is Context-Free
نویسندگان
چکیده
Let A be a finite, totally ordered alphabet, and let P be the lexicographic ordering on A*. Let X be a subset of A*. The language of minimal words of X is the subset of X composed of the lexicographically minimal word of X for each length: Min(X)=[x # X | \w # X, |w|=|x| O xPw]. The aim of this paper is to prove that if L is a context-free language, then the language Min(L) context-free. ] 1997
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ورودعنوان ژورنال:
- J. Comput. Syst. Sci.
دوره 55 شماره
صفحات -
تاریخ انتشار 1997