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Regular expressions and finite automata, Context-free grammars and push-down automata, Regular and context-free languages, Pumping lemma, Turing machines and undecidability.

$$\scriptsize{\overset{{\large{\textbf{Mark Distribution in Previous GATE}}}}{\begin{array}{|c|c|c|c|c|c|c|c|}\hline
\textbf{Year}& \textbf{2022} & \textbf{2021-1}&\textbf{2021-2}&\textbf{2020}&\textbf{2019}&\textbf{2018}&\textbf{2017-1}&\textbf{2017-2}&\textbf{2016-1}&\textbf{2016-2}&\textbf{Minimum}&\textbf{Average}&\textbf{Maximum}
\\\hline\textbf{1 Mark Count} & 2 &2&3&3&2&2&2&3&3&3&2&2.5&3
\\\hline\textbf{2 Marks Count} & 3 &3&4&3&3&3&5&3&3&3&3&3.3&5
\\\hline\textbf{Total Marks} & 8 &8&11&9&8&8&12&9&9&9&\bf{8}&\bf{9.1}&\bf{12}\\\hline
\end{array}}}$$

Recent questions in Theory of Computation

0 votes
1 answer
5201
6 votes
2 answers
5202
Given a regular grammar $G_1$ and a context free grammar $G_2$, the problem of deciding if $L(G_1)$ is a proper subset of $L(G_2)$ is:DecidableUndecidable but semi-decida...
4 votes
1 answer
5203
0 votes
1 answer
5206
1 votes
2 answers
5207
PDA can be used for:infix to postfix conversionimplementing recursive function callsevaluating arithmetic expressionsall of the above
0 votes
0 answers
5208
By reading any string, which of the following is possible for a Turing Machine?TM halts in Final StateTM halts in Non Final StateTM enters into Infinite LoopAll of these
3 votes
1 answer
5209
Consider the following CFG :$S \rightarrow AB$$A \rightarrow BC \mid a$$B \rightarrow CC \mid b$$C \rightarrow a \mid AB$The Rank of Variable $A$ is:$2$$3$$4$not possible...
2 votes
1 answer
5210
Which of the following is not a Regular Expression?$[(a+b)^* – (aa+bb)]^*$$[(0+1) – (0b + a1)^* (a+b)]^*$$(01+11+10)^*$$(1+2+0)^* (1+2)^*$
4 votes
2 answers
5211
Consider the following grammar: $G$ $E \rightarrow E+E \mid E-E \mid E^*E \mid (E)\mid \text{id}$The number of derivation trees for the string $\text{id} +\text{id} ^* \t...
3 votes
2 answers
5212
Total Recursive Functions are similar to:Recursive LanguagesRecursive Enumerable LanguagesCannot relate the twoNone
0 votes
3 answers
5213
Which one is a correct statement in terms of accepting powers of DPDA and NPDA?DPDA and NPDA are equalDPDA and NPDA are not comparableDPDA < NPDADPDA NPDA
2 votes
1 answer
5214
The Minimal Finite Automata accepting the set of all strings over $(0+1)^*$ that do NOT have the sub-string $0001$ has:$5$ states$6$ states$7$ states$9$ states
2 votes
2 answers
5215
1 votes
1 answer
5216
The regular set $A =(01+1)^*$ and the regular set $B =((01)^*1^*)^*$Which of the following statements is TRUE?$A$ is a subset of $B$$B$ is a subset of $A$$A$ and $B$ are ...
2 votes
2 answers
5217
Identify the Regular Expression among the following which denotes ALL strings of $a$'s and $b$'s, where each string contains at least $2$ $b$'s:$(a+b)^*ba^*b$$(a+b)^*ba^*...
6 votes
1 answer
5219
An NFA has $10$ states out of which $3$ are final states. The maximum number of final states in converted DFA is:$895$$894$$896$$897$