51 Queues 1 True or False a A queue is a first in first out

5.1 Queues 1. True or False? a. A queue is a “first in, first out\" structure. b. The element that has been in a queue the longest is at the \"rear\" of the queue. c. If you enqueue five elements into an empty queue and then dequeue five elements, the queue will be empty again d. If you enqueue five elements into an empty queue and then perform the isEmpty operation five times, the queue will be empty again e. The enqueue operation should be classified as a \"transformer.\" f. The isEmpty operation should be classified as a \"transformer.\" g. The dequeue operation should be classified as an \"observer.\" h. If we first enqueue elementA into an empty queue and then enqueue elementB, the front of the queue is elementA

Solution

5.1. a) A queue is a \"first in, first out\" structure
True
The element that passed first will be served first in queue structure

5.1. b) The element that has been in a queue the longest is at the \"rear\" of the queue
False
No, the element which has been in a queue the longest will be at front. Last in element will be at rear.

5.1. c) If you enqueue five elements into an empty queue and then dequeue five elements, the queue will be empty again.
True
Initially queue is empty
push 5 elements -> Queue has 5 elements
pop 5 elements -> Queue is empty again

5.1. d) If you enqueue five elements into an empty queue and then perform the isEmpty operationfive times, the queue will be empty again
False
isEmpty is a check that tells whether the queue is empty or not. That\'s it. It doesn\'t perform any operation. So, queue remains the same.