2025 question paper
Formal Language & Automata Theory
28 questions
Q1a. Which of the following is the smallest unit in the definition of a language? (i) Grammar (ii) Alphabet (iii) String (iv) Production20252m
Module 1: Introduction, Regular languages and finite automata
View this question on its own page →Which of the following is the smallest unit in the definition of a language?
(i) Grammar
(ii) Alphabet
(iii) String
(iv) ProductionQ1b. A language is a (i) Set of alphabets (ii) Set of strings over an alphabet (iii) Set of grammars (iv) Set of automata20252m
Module 1: Introduction, Regular languages and finite automata
View this question on its own page →A language is a
(i) Set of alphabets
(ii) Set of strings over an alphabet
(iii) Set of grammars
(iv) Set of automataQ1c. Which grammar type is the most powerful? (i) Type-0 (ii) Type-1 (iii) Type-2 (iv) Type-320252m
Module 1: Introduction, Regular languages and finite automata
View this question on its own page →Which grammar type is the most powerful?
(i) Type-0
(ii) Type-1
(iii) Type-2
(iv) Type-3Q1d. Epsilon (\varepsilon) transitions are allowed in (i) DFA only (ii) Both DFA and NFA (iii) NFA only (iv) None20252m
Module 1: Introduction, Regular languages and finite automata
View this question on its own page →Epsilon () transitions are allowed in
(i) DFA only
(ii) Both DFA and NFA
(iii) NFA only
(iv) NoneQ1e. Context-Free Grammars are equivalent to (i) Finite Automata (ii) Turing Machines (iii) Linear Bounded Automata (iv) Pushdown Automata20252m
Module 2: Context-free languages and pushdown automata
View this question on its own page →Context-Free Grammars are equivalent to
(i) Finite Automata
(ii) Turing Machines
(iii) Linear Bounded Automata
(iv) Pushdown AutomataQ1f. Pumping Lemma for CFLs is used to prove a language is (i) Not Context-Free (ii) Regular (iii) Decidable (iv) Turing recognizable20252m
Module 2: Context-free languages and pushdown automata
View this question on its own page →Pumping Lemma for CFLs is used to prove a language is
(i) Not Context-Free
(ii) Regular
(iii) Decidable
(iv) Turing recognizableQ1g. Which of the following requires context sensitivity? (i) a^n b^n (ii) a^n b^n c^n (iii) (a+b)^* (iv) a^*20252m
Module 3: Context sensitive langauges
View this question on its own page →Which of the following requires context sensitivity?
(i)
(ii)
(iii)
(iv)Q1h. Recursively Enumerable languages are also called (i) Turing Recognizable (ii) Turing Decidable (iii) Regular (iv) Context-Free20252m
Module 4: Turing machines
View this question on its own page →Recursively Enumerable languages are also called
(i) Turing Recognizable
(ii) Turing Decidable
(iii) Regular
(iv) Context-FreeQ1i. The Halting Problem is (i) Decidable (ii) Undecidable (iii) Context-Free (iv) Regular20252m
Module 5: Undecidability
View this question on its own page →The Halting Problem is
(i) Decidable
(ii) Undecidable
(iii) Context-Free
(iv) RegularQ1j. Which of the following is used to prove many undecidability results? (i) Pumping Lemma (ii) Rice's Theorem (iii) Chomsky Normal Form (iv) Subset Construction20252m
Module 5: Undecidability
View this question on its own page →Which of the following is used to prove many undecidability results?
(i) Pumping Lemma
(ii) Rice's Theorem
(iii) Chomsky Normal Form
(iv) Subset ConstructionQ2a. Define the terms: Alphabet, Language, Grammar, and Derivation. Explain the relationship between them with suitable examples.20257m
Module 1: Introduction, Regular languages and finite automata
View this question on its own page →Define the terms: Alphabet, Language, Grammar, and Derivation. Explain the relationship between them with suitable examples.
Q2b. Explain Chomsky Hierarchy of languages with examples of each type and their corresponding automata.20257m
Module 1: Introduction, Regular languages and finite automata
View this question on its own page →Explain Chomsky Hierarchy of languages with examples of each type and their corresponding automata.
Q3a. Explain the concept of a Finite Automaton. List and describe its main components. Also, differentiate between Deterministic Finite Automaton and Non-deterministic Finite Automaton with suitable examples.20257m
Module 1: Introduction, Regular languages and finite automata
View this question on its own page →Explain the concept of a Finite Automaton. List and describe its main components. Also, differentiate between Deterministic Finite Automaton and Non-deterministic Finite Automaton with suitable examples.
Q3b. Construct a DFA that accepts all strings over \{0,1\} containing an even number of 0s and an odd number of 1s. Also, write its formal 5-tuple definition.20257m
Module 1: Introduction, Regular languages and finite automata
View this question on its own page →Construct a DFA that accepts all strings over containing an even number of 0s and an odd number of 1s. Also, write its formal 5-tuple definition.
Q4a. Convert the regular expression (a + b)abb(a + b) into an equivalent DFA. Show all steps.20257m
Module 1: Introduction, Regular languages and finite automata
View this question on its own page →Convert the regular expression into an equivalent DFA. Show all steps.
Q4b. Using Pumping Lemma, prove that the language L = \{0^{n}1^{n} \mid n \ge 0\} is not regular.20257m
Module 1: Introduction, Regular languages and finite automata
View this question on its own page →Using Pumping Lemma, prove that the language is not regular.
Q5a. Explain how ambiguity arises in the grammar E \rightarrow E + E \mid E \times E \mid id \mid (E). Remove the ambiguity by rewriting the grammar.20257m
Module 2: Context-free languages and pushdown automata
View this question on its own page →Explain how ambiguity arises in the grammar . Remove the ambiguity by rewriting the grammar.
Q5b. Using Pumping Lemma for CFLs, prove that L = \{a^{n}b^{n}c^{n} \mid n \ge 0\} is not context-free.20257m
Module 2: Context-free languages and pushdown automata
View this question on its own page →Using Pumping Lemma for CFLs, prove that is not context-free.
Q6a. Explain Linear Bounded Automata and its relationship with Context-Sensitive Languages.20257m
Module 3: Context sensitive langauges
View this question on its own page →Explain Linear Bounded Automata and its relationship with Context-Sensitive Languages.
Q6b. Explain the basic model of a Turing Machine with its formal 7-tuple definition.20257m
Module 4: Turing machines
View this question on its own page →Explain the basic model of a Turing Machine with its formal 7-tuple definition.
Q7a. Design a Turing Machine that accepts the language L = \{a^{n}b^{n} \mid n \ge 0\}. Show the transition diagram/table and trace for input aabb.20257m
Module 4: Turing machines
View this question on its own page →Design a Turing Machine that accepts the language . Show the transition diagram/table and trace for input aabb.
Q7b. State and explain the Church-Turing Thesis.20257m
Module 4: Turing machines
View this question on its own page →State and explain the Church-Turing Thesis.
Q8a. Explain the concept of Universal Turing Machine. How does it help in proving undecidability?20257m
Module 5: Undecidability
View this question on its own page →Explain the concept of Universal Turing Machine. How does it help in proving undecidability?
Q8b. Discuss the power and limitations of Turing Machines. Compare Turing Machines with Pushdown Automata.20257m
Module 4: Turing machines
View this question on its own page →Discuss the power and limitations of Turing Machines. Compare Turing Machines with Pushdown Automata.
Q9a. Write a short note on: Pushdown Automata20257m
Module 2: Context-free languages and pushdown automata
View this question on its own page →Write a short note on:
Pushdown Automata
Q9b. Write a short note on: Rice's theorem20257m
Q9c. Write a short note on: Minimization of finite automata20257m
Module 1: Introduction, Regular languages and finite automata
View this question on its own page →Write a short note on:
Minimization of finite automata
Q9d. Write a short note on: Closure properties of CFLs20257m
Module 2: Context-free languages and pushdown automata
View this question on its own page →Write a short note on:
Closure properties of CFLs