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 2
MCQ (Single Correct Answer)
+1
-0.3
Let $$A\,\,{ \le _m}\,\,B$$ denotes that language $$A$$ is mapping reducible (also known as many-to-one reducible) to language $$B.$$ Which one of the following is FALSE?
A
If $$A\,\,{ \le _m}\,\,B$$ and $$B$$ is recursive then $$A$$ is recursive.
B
If $$A\,\,{ \le _m}\,\,B$$ and $$A$$ is undecidable then $$B$$ is un-decidable.
C
If $$A\,\,{ \le _m}\,\,B$$ and $$B$$ is recursively enumerable then $$A$$ is recursively enumerable.
D
If $$A\,\,{ \le _m}\,\,B$$ and $$B$$ is not recursively enumerable then $$A$$ is not recursively enumerable.
2
GATE CSE 2013
MCQ (Single Correct Answer)
+1
-0.3
Which of the following statements is/are FALSE?
$$1.$$ For every non-deterministic Turing machine, there exists an equivalent deterministic Turing machine
$$2.$$ Turing recognizable languages are closed under union and complementation
$$3.$$ Turing decidable languages are closed under intersection and complementation
$$4.$$ Turing recognizable languages are closed under union and intersection
A
$$1$$ and $$4$$ only
B
$$1$$ and $$3$$ only
C
$$2$$ only
D
$$3$$ only
3
GATE CSE 2008
MCQ (Single Correct Answer)
+1
-0.3
Which of the following is true for the language $$\left\{ {{a^p}} \right.\left| P \right.$$ prime $$\left. \, \right\}$$?
A
It is not accepted by a Turing machine
B
It is regular but not context-free
C
It is context-free but not regular
D
It is neither regular nor context-free, but accepted by a Turing machine
4
GATE CSE 2003
MCQ (Single Correct Answer)
+1
-0.3
If the strings of a language $$L$$ can be effectively enumerated in lexicographic (i.e., alphabetic$$(c)$$ order, which of the following statements is true?
A
$$L$$ is necessarily finite
B
$$L$$ is regular but not necessarily finite
C
$$L$$ is context free but not necessarily regular
D
$$L$$ is recursive but not necessarily 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