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 2014 Set 3
MCQ (Single Correct Answer)
+2
-0.6
Consider the following languages over the alphabet $$\sum { = \left\{ {0,\,1,\,c} \right\}:} $$
$$\eqalign{ & {L_1} = \left\{ {{0^n}\,{1^n}\,\left| {n \ge } \right.0} \right\} \cr & {L_2} = \left\{ {wc{w^r}\,\left| {w \in \left\{ {0,\,1} \right\}{}^ * } \right.} \right\} \cr & {L_3} = \left\{ {w{w^r}\,\left| {w \in \left\{ {0,\,1} \right\}{}^ * } \right.} \right\} \cr} $$

Here, $${w^r}$$ is the reverse of the string $$w.$$ Which of these languages are deterministic Context- free languages?

A
None of the languages
B
$$(B)$$ Only $${L_1}$$
C
Only $${L_1}$$ and $${L_2}$$
D
All the three languages.
2
GATE CSE 2013
MCQ (Single Correct Answer)
+2
-0.6
Consider the $$DFA$$ $$A$$ given below. GATE CSE 2013 Theory of Computation - Push Down Automata and Context Free Language Question 30 English

Which of the following are FALSE?
$$1.$$ Complement of $$L(A)$$ is context - free.
$$2.$$ $$L(A)$$ $$ = \left( {{{11}^ * }0 + 0} \right)\left( {0 + 1} \right){}^ * {0^ * }\left. {{1^ * }} \right)$$
$$3.$$ For the language accepted by $$A, A$$ is the minimal $$DFA.$$
$$4.$$ $$A$$ accepts all strings over $$\left\{ {0,1} \right\}$$ of length at least $$2.$$

A
$$1$$ and $$3$$ only
B
$$2$$ and $$4$$ only
C
$$2$$ and $$3$$ only
D
$$3$$ and $$4$$ only
3
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
4
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
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