NIELIT 2017 DEC Scientist B - Section B: 56

Question

Which of the following statement is true?

• A. Deterministic context free language are closed under complement.
• B. Deterministic context free language are not closed under Union.
• C. Deterministic context free language are closed under intersection with regular set.
• D. All of the options

Comments

As per the question, second option is "Deterministic context free language is not closed under union". So all the options mentioned in NIELIT Scientist-B Dec 2017_59 was true. Answer is D.

Answer 1

As per the question, second option is "Deterministic context free language is not closed under union".

→ Deterministic Context free language are closed under complement
→ Deterministic Context free language are not closed under union
→ Deterministic Context free language are closed under intersection with regular set

correct option -D

Answer 2

Option A and C both are true.

Comments

Deterministic Context Free Language are NOT closed under intersection. Option C is false. Option B, however, is correct because DCFL are not closed under union either.

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Intersection with regular set - dcfl is closed under this.

Answer 3

Deterministic context free languages are closed under complementation . So correct answer will be A option

Comments

DCFL is also closed under "Union and Intersection with regular set".