Question

________ data type is used to implement a Queue data structure in Python?

• A. Sets
• B. Dictionary
• C. Tuple
• D. List

Answer 1

The Correct Option is D

To implement a Queue data structure in Python, the List data type is most commonly used. Below is a simple illustration showing how a List can effectively implement a Queue:

Operation	Description
Enqueue	Adding an element to the end of the list using the append() method.
Dequeue	Removing an element from the start of the list using the pop(0) method.
Peek	Accessing the first element using the index [0].

Example implementation:

queue=[]#Enqueue elementsqueue.append(1)queue.append(2)queue.append(3)#Dequeue elementfirst_elem=queue.pop(0)#Peek at the next elementnext_elem=queue[0]

This flexibility and simplicity in implementation make Lists the preferred data type for Queues in Python.

Answer 2

The data type most commonly used to implement a Queue data structure in Python is List.

Additional Context:

• List Implementation (4):
  • Basic queue operations using list methods:
    • append() for enqueue (add to rear)
    • pop(0) for dequeue (remove from front)
  • Simple but inefficient for large queues (O(n) for pop(0))
• Better Alternatives:
  • collections.deque (optimized for O(1) at both ends)
  • queue.Queue (thread-safe implementation)
• Why Other Options Are Poor Choices:
  • Sets (1): Unordered, no position control
  • Dictionary (2): Key-value pairs, not sequential
  • Tuple (3): Immutable (can't modify after creation)
• Example List-Based Queue:

  queue = []
  queue.append(10)  # Enqueue
  queue.append(20)
  item = queue.pop(0)  # Dequeue → 10
      

Correct Answer: (4) List.