Theory of Automata MCQs with Answers
Practice important Theory of Automata MCQs with answers and explanations.
Chapter: 40
Q501:
What is the role of the conversion form in the context of PDA and CFG?
A. It facilitates the conversion of a PDA to a CFG and vice versa
B. It simplifies the PDA without affecting CFG conversion
C. It removes the need for CFG conversion
D. It changes the language accepted by the PDA
Correct Answer:
A
Chapter: 40
Q502:
How does the PDA ensure that the STACK does not pop beneath the bottom of STACK symbol $?
A. By replacing the symbol $ if it is ever popped and never popping beneath it
B. By allowing unlimited popping of STACK
C. By ignoring the STACK symbol $
D. By replacing the symbol $ with another symbol
Correct Answer:
A
Chapter: 40
Q503:
What is the key condition for a PDA to be in conversion form regarding branching?
A. All branching must occur at READ or HERE states, not at POP states
B. Branching can occur at any state
C. Branching is not allowed
D. Branching only occurs at POP states
Correct Answer:
A
Chapter: 40
Q504:
What is a common step in the conversion process of a PDA to conversion form?
A. Ensuring every READ or HERE state is followed by a POP state
B. Adding more REJECT states
C. Ignoring all non-deterministic choices
D. Changing the language accepted by the PDA
Correct Answer:
A
Chapter: 41
Q505:
What defines a PDA in conversion form?
A. Conditions such as having exactly one ACCEPT state and no REJECT states
B. Having multiple ACCEPT states and REJECT states
C. Having no READ or HERE states
D. Having no POP states
Correct Answer:
A
Chapter: 41
Q506:
What is the role of the bottom of STACK symbol ($) in the PDA conversion form?
A. It is placed on the STACK to prevent popping beneath it and is only popped out before ACCEPT
B. It is used to mark the end of the input string
C. It is used to replace the symbol $ if it is ever popped
D. It is ignored during processing
Correct Answer:
A
Chapter: 41
Q507:
In the PDA conversion form, what must occur before the machine can accept the input string?
A. The entire input string must be read
B. Only a part of the input string needs to be read
C. The input string can be ignored
D. The machine accepts the input immediately
Correct Answer:
A
Chapter: 41
Q508:
What is the primary purpose of converting a PDA to its conversion form?
A. To simplify its representation and ensure it adheres to specific conditions
B. To make the PDA non-deterministic
C. To allow multiple REJECT states
D. To eliminate the need for ACCEPT states
Correct Answer:
A
Chapter: 41
Q509:
How are paths represented in a PDA in conversion form?
A. As sequences of rows from the summary table
B. As strings of input letters
C. As sequences of READ and HERE states
D. As paths through the TAPE only
Correct Answer:
A
Chapter: 41
Q510:
What must be ensured for a row sequence to be considered a valid path in the PDA?
A. The sequence must be joint consistent and STACK consistent
B. The sequence must only be joint consistent
C. The sequence must only be STACK consistent
D. The sequence must contain only READ states
Correct Answer:
A
Chapter: 41
Q511:
In the context of PDA, what does "joint consistent" mean?
A. The rows meet end to end without any gaps
B. The rows are read from the TAPE in order
C. The rows are STACK consistent
D. The rows are randomly ordered
Correct Answer:
A
Chapter: 41
Q512:
How does a row sequence like Row5 Row5 Row3 Row6 relate to the row language?
A. It does not represent a valid path if it is not joint consistent or STACK consistent
B. It always represents a valid path
C. It is always joint consistent
D. It is always STACK consistent
Correct Answer:
A
Chapter: 41
Q513:
What must be defined before determining the CFG that generates the language accepted by a PDA?
A. The CFG that generates the row language
B. The summary table of the PDA
C. The list of ACCEPT states
D. The list of REJECT states
Correct Answer:
A
Chapter: 41
Q514:
What does a valid path in the row language start and end with?
A. It starts with Row1 and ends with Row7
B. It starts with any row and ends with Row1
C. It starts with Row7 and ends with Row1
D. It starts with Row2 and ends with Row6
Correct Answer:
A
Chapter: 41
Q515:
How are joints in a PDA path described?
A. They include START, READ, HERE, and ACCEPT states
B. They include only READ and HERE states
C. They include only START and ACCEPT states
D. They are randomly placed
Correct Answer:
A
Chapter: 41
Q516:
What is a key characteristic of a PDA's path in the conversion form?
A. Each path segment includes exactly one character popped and any number of characters pushed
B. Each path segment includes multiple characters popped and no characters pushed
C. Each path segment includes no characters popped
D. Each path segment includes multiple characters pushed and no characters popped
Correct Answer:
A
Chapter: 42
Q517:
What is the alphabet of the Row language in Chapter 15?
A. {Row1, Row2, …, Row7}
B. {Row1, Row2, …, Row6}
C. {Row1, Row2, …, Row8}
D. {Row1, Row2, …, Row5}
Correct Answer:
A
Chapter: 42
Q518:
What does the nonterminal Net(X, Y, Z) represent in the context of the Row language?
A. The net STACK effect between two joints
B. The starting state of a PDA
C. The acceptance condition of a PDA
D. The termination state of a CFG
Correct Answer:
B
Chapter: 42
Q519:
In a PDA conversion form, how many ACCEPT states are allowed?
A. None
B. One
C. Two
D. Three
Correct Answer:
B
Chapter: 42
Q520:
What is required to be true for a PDA to be considered in conversion form regarding POP states?
A. No POP state should exist
B. POP states can follow each other without any READ or HERE in between
C. POP states must be separated by READs or HEREs
D. POP states must be immediately preceded by PUSH states
Correct Answer:
C