A queue performs the following commands (in pseudo-code): enqueue 4, 6, 8, 3, 1
Dequeue three elements
Enqueue 3, 1, 5, 6
Dequeue two elements
What number is now at the front of the queue?
A) 3
B) 4
C) 5
D) 6

Question

Quizplus · Accepted Answer

After enqueueing 4, 6, 8, 3, 1 and dequeuing three elements, the queue contains 3 and 1. Then, enqueueing 3, 1, 5, 6, we have the queue 3, 1, 3, 1, 5, 6. When we dequeue two elements, we have the queue 3, 1, 5, 6. Therefore, the number at the front of the queue is 3.

A Queue Performs the Following Commands (In Pseudo-Code): Enqueue 4