An undecidable property of context-free languages
نویسنده
چکیده
We prove that there exists no algorithm to decide whether the language generated by a context-free grammar is dense with respect to the lexicographic ordering. As a corollary to this result, we show that it is undecidable whether the lexicographic orderings of the languages generated by two context-free grammars have the same order type.
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ورودعنوان ژورنال:
- CoRR
دوره abs/1004.1736 شماره
صفحات -
تاریخ انتشار 2010