Theory of Automata MCQs with Answers
Practice important Theory of Automata MCQs with answers and explanations.
Chapter: 39
Q481:
In the given PDA example, what is the initial state of the PDA?
A. START
B. ACCEPT
C. REJECT
D. READ1
Correct Answer:
A
Chapter: 39
Q482:
What is the role of the POP state in the PDA corresponding to the given CFG?
A. To accommodate productions by replacing nonterminals or reading letters
B. To start the machine
C. To accept the string
D. To reject the string
Correct Answer:
A
Chapter: 39
Q483:
In the given PDA, what does the PUSH S state do?
A. Adds the nonterminal S to the STACK
B. Pops the nonterminal S from the STACK
C. Reads the nonterminal S from the TAPE
D. Transitions to the ACCEPT state
Correct Answer:
A
Chapter: 39
Q484:
How is the word 'aab' processed in the PDA?
A. By performing a series of PUSH and POP operations according to CFG rules
B. By only reading from the TAPE
C. By only pushing characters onto the STACK
D. By ignoring the CFG
Correct Answer:
A
Chapter: 39
Q485:
In the PDA for the CFG S → XY, what does the state PUSH X do?
A. Adds the nonterminal X to the STACK
B. Removes the nonterminal X from the STACK
C. Reads the nonterminal X from the TAPE
D. Transitions to the REJECT state
Correct Answer:
A
Chapter: 39
Q486:
What is the purpose of introducing nonterminals A and B in the CFG conversion?
A. To convert the CFG into CNF
B. To add new terminals to the CFG
C. To remove existing terminals from the CFG
D. To change the language of the CFG
Correct Answer:
A
Chapter: 39
Q487:
In the PDA corresponding to the CFG S → XY, what does the state READ2 do?
A. Reads the letter from the TAPE
B. Pops a letter from the STACK
C. Pushes a letter onto the STACK
D. Transitions to the REJECT state
Correct Answer:
A
Chapter: 39
Q488:
How is the production S → XY handled in the PDA?
A. By pushing X and Y onto the STACK
B. By popping X and Y from the STACK
C. By reading X and Y from the TAPE
D. By accepting the string
Correct Answer:
A
Chapter: 39
Q489:
What does the PDA do when it encounters the production X → AX?
A. It pushes A and X onto the STACK
B. It pops A and X from the STACK
C. It reads A and X from the TAPE
D. It transitions to the REJECT state
Correct Answer:
A
Chapter: 39
Q490:
In the example, what does the state PUSH A do in the PDA for the CFG?
A. Adds the nonterminal A to the STACK
B. Removes the nonterminal A from the STACK
C. Reads the nonterminal A from the TAPE
D. Transitions to the ACCEPT state
Correct Answer:
A
Chapter: 39
Q491:
How is the PDA's STACK used in processing the word 'aaab'?
A. By performing PUSH and POP operations based on CFG rules
B. By only reading from the TAPE
C. By only pushing characters onto the STACK
D. By ignoring CFG rules
Correct Answer:
A
Chapter: 39
Q492:
What happens when the PDA enters the ACCEPT state?
A. The string is accepted
B. The string is rejected
C. The machine continues to run
D. The machine pauses
Correct Answer:
A
Chapter: 40
Q493:
What is the conversion form of a PDA?
A. A PDA in which every READ or HERE is followed by a POP and has specific conditions
B. A PDA that accepts only deterministic languages
C. A PDA with multiple REJECT states
D. A PDA that starts with an ACCEPT state
Correct Answer:
A
Chapter: 40
Q494:
What does the HERE state in a PDA do?
A. It is placed in the middle of any edge to facilitate conversion to standard form
B. It represents an ACCEPT state
C. It replaces a POP state
D. It starts the PDA
Correct Answer:
A
Chapter: 40
Q495:
In the conversion form of a PDA, what must follow every READ or HERE state?
A. A POP state
B. Another READ state
C. A PUSH state
D. A REJECT state
Correct Answer:
A
Chapter: 40
Q496:
What is the purpose of the bottom of STACK symbol ($) in the PDA conversion form?
A. To prevent popping the STACK beneath this symbol and to be replaced if popped
B. To start the PDA
C. To mark the end of the input string
D. To accept the input string
Correct Answer:
A
Chapter: 40
Q497:
How is the input string processed in a PDA converted to conversion form?
A. The entire input string must be read before acceptance
B. The input string is accepted immediately
C. The input string is only partially read
D. The input string is ignored
Correct Answer:
A
Chapter: 40
Q498:
What happens when a PDA is converted into conversion form and the STACK is initially empty?
A. A bottom of STACK symbol $ is placed on the STACK
B. The PDA is immediately accepted
C. The PDA is rejected
D. The STACK is ignored
Correct Answer:
A
Chapter: 40
Q499:
What must be ensured when converting a PDA to conversion form regarding the edges?
A. Every edge leading out of READ or HERE states goes directly into a POP state
B. Edges can lead to any state
C. Edges are ignored in conversion form
D. Edges can lead to multiple POP states
Correct Answer:
A
Chapter: 40
Q500:
In the conversion form of a PDA, how are non-deterministic choices handled?
A. They occur at READ or HERE states, not at POP states
B. They occur at POP states
C. They are not allowed
D. They occur at START states
Correct Answer:
A