Question

In Python, ________ module needs to be imported for implementing a Double-Ended Queue?

• A. counter
• B. collections
• C. random
• D. numpy

Answer 1

The Correct Option is B

In Python, the collections module needs to be imported for implementing a Double Ended Queue (Deque).

Additional Context:

• Collections Module (Option 2):
  • Contains specialized container datatypes
  • Provides deque class for double-ended queues
• Deque Implementation:

  from collections import deque
  d = deque([1, 2, 3])
  d.appendleft(0)  # Add to front
  d.append(4)      # Add to end
      

• Key Features:
  • O(1) complexity for append/pop at both ends
  • Thread-safe for appends/pops
  • Max length can be specified
• Why Other Options Are Incorrect:
  • counter (1): For counting hashable objects
  • random (3): For generating random numbers
  • numpy (4): For numerical computing

Correct Answer: (2) collections.