Theory of Computation
Finite Automata and Regular Language
Marks 1Marks 2Marks 5
Push Down Automata and Context Free Language
Marks 1Marks 2
Undecidability
Marks 1Marks 2
Recursively Enumerable Language and Turing Machine
Marks 1Marks 2
1
GATE CSE 2011
MCQ (Single Correct Answer)
+2
-0.6
Consider the languages $${L_1}$$, $${L_2}$$ and $${L_3}$$ are given below. $$$\eqalign{ & {L_1} = \left\{ {{0^p}{1^q}\left| {p,q \in N} \right.} \right\} \cr & {L_2} = \left\{ {{0^p}{1^q}\left| {p,q \in N} \right.\,\,and\,\,p = q} \right\}\,\,and \cr & {L_3} = \left\{ {{0^p}{1^q}{0^r}\left| {p,q,r\, \in N\,\,\,and\,\,\,p = q = r} \right.} \right\}. \cr} $$$

Which of the following statements is not TRUE?

A
Pushdown automata $$(PDA)$$ can be used to recognize $${L_1}$$ and $${L_2}$$
B
$${L_1}$$ is a regular language
C
All the three languages are context free
D
Turing machines can be used to recognize all the languages
2
GATE CSE 2010
MCQ (Single Correct Answer)
+2
-0.6
Consider the languages $$$\eqalign{ & {L_1} = \left\{ {{0^i}{1^j}\,\left| {i \ne j} \right.} \right\},\,{L_2} = \left\{ {{0^i}{1^j}\,\left| {i = j} \right.} \right\}, \cr & {L_3} = \left\{ {{0^i}{1^j}\,\left| {i = 2j + 1} \right.} \right\}, \cr & {L_4} = \left\{ {{0^i}{1^j}\,\left| {i \ne 2j} \right.} \right\}, \cr} $$$
A
only $${L_2}$$ is context free
B
only $${L_2}$$ and $${L_3}$$ are context free
C
only $${L_1}$$ and $${L_2}$$ are context free
D
all are context free
3
GATE CSE 2008
MCQ (Single Correct Answer)
+2
-0.6
Match the following List-$${\rm I}$$ with List - $${\rm II}$$

List-$${\rm I}$$
$$E)$$ Checking that identifiers are declared before their
$$F)$$ Number of formal parameters in the declaration of a function agrees with the number of actual parameters in a use of that function
$$G)$$ Arithmetic expression with matched pairs of parentheses
$$H)$$ Palindromes

List-$${\rm II}$$
$$P)$$ $$L = \left\{ {{a^n}{b^m}{c^n}{d^m}\,|\,n \ge 1,m \ge 1} \right\}$$
$$Q)$$ $$X \to XbX\,|\,XcX\,|\,dXf\,|g$$
$$R)$$ $$L = \left\{ {www\,|\,w \in \left( {a\,|\,b} \right){}^ * } \right\}$$
$$S)$$ $$X \to bXB\,|\,cXc\,|\,\varepsilon $$

A
$$E - P,\,F - R,\,G - Q,\,H - S$$
B
$$E - R,\,F - P,\,G - S,\,H - Q$$
C
$$E - R,\,F - P,\,G - Q,\,H - S$$
D
$$E - P,\,F - R,\,G - S,\,H - Q$$
4
GATE CSE 2008
MCQ (Single Correct Answer)
+2
-0.6
Which of the following statements are true?
$$1.$$ Every left-recursive grammar can be converted to a right-recursive grammar and vice-versa
$$2.$$ All ε-productions can be removed from any context-free grammar by suitable transformations
$$3.$$ The language generated by a context-free grammar all of whose productions are of the form $$X \to w$$ or $$X \to wY$$ (where, $$w$$ is a string of terminals and $$Y$$ is a non terminal), is always regular
$$4.$$ The derivation trees of strings generated by a context-free grammar in Chomsky Normal Form are always binary trees
A
$$1,2,3$$ and $$4$$
B
$$2, 3$$ and $$4$$ only
C
$$1,3$$ and $$4$$ only
D
$$1,2$$ and $$4$$ only
GATE CSE Subjects
Theory of Computation
Operating Systems
Algorithms
Digital Logic
Database Management System
Data Structures
Computer Networks
Software Engineering
Compiler Design
Web Technologies
General Aptitude
Discrete Mathematics
Programming Languages
Computer Organization