Which one of the following problems is undecidable?

GATE · 2014 · CS · Set 3 · Computer Science & IT

1. A.

   Deciding if a given context-free grammar is ambiguous.

2. B.

   Deciding if a given string is generated by a given context-free grammar.

3. C.

   Deciding if the language generated by a given context-free grammar is empty.

4. D.

   Deciding if the language generated by a given context-free grammar is finite.

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