1
GATE CSE 2020
MCQ (Single Correct Answer)
+1
-0.33
Consider the following statements.

I. If L1 $$ \cup $$ L2 is regular, then both L1 and L2 must be regular.

II. The class of regular languages is closed under infinite union.

Which of the above statements is/are TRUE?
A
I only
B
II only
C
Both I and II
D
Neither I nor II
2
GATE CSE 2019
MCQ (Single Correct Answer)
+1
-0.33
If L is a regular language over Σ = {a, b}, which one of the following languages is NOT regular?
A
Suffix (L) = {y ∈ Σ* such that xy ∈ L}
B
{wwR │w ∈ L}
C
Prefix (L) = {x ∈ Σ*│∃y ∈ Σ* such that xy ∈ L}
D
L ∙ LR = {xy │ x ∈ L, yR ∈ L}
3
GATE CSE 2019
MCQ (Single Correct Answer)
+1
-0.33
For Σ = {a, b}, let us consider the regular language L = {x | x = a2+3k or x = b10+12k, k ≥ 0}. Which one of the following can be a pumping length (the constant guaranteed by the pumping lemma) for L?
A
9
B
5
C
24
D
3
4
GATE CSE 2016 Set 1
MCQ (Single Correct Answer)
+1
-0.3
Which one of the following regular expressions represents the language: the set of all binary strings having two consecutive $$0s$$ and two consecutive $$1s?$$
A
$$\left( {0 + 1} \right){}^ * 0011\left( {0 + 1} \right){}^ * + \left( {0 + 1} \right){}^ * 1100\left( {0 + 1} \right){}^ * $$
B
$$\left( {0 + 1} \right){}^ * \left( {00\left( {0 + 1} \right){}^ * 11 + 11\left( {0 + 1} \right){}^ * \left. {00} \right)} \right.\left( {0 + 1} \right){}^ * $$
C
$$\left( {0 + 1} \right){}^ * 00\left( {0 + 1} \right){}^ * + \left( {0 + 1} \right){}^ * 11\left( {0 + 1} \right){}^ * $$
D
$$00\left( {0 + 1} \right){}^ * 11 + 11\left( {0 + 1} \right){}^ * 00$$
GATE CSE Subjects
Software Engineering
Web Technologies
EXAM MAP