Data Structures · Question 3 · Easy
Data Structures question 3
Starting with an empty queue: enqueue(A), enqueue(B), enqueue(C), dequeue(), enqueue(D), dequeue(). Which element is now at the front of the queue?
- C
- B
- D
- A
Answer and explanation
Answer: A. C
Explanation: Queue becomes A B C, then B C after the first dequeue, B C D after enqueue(D), and C D after the second dequeue. The front is C.
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