How does FIFO describe queue?
FIFO stands for First In First Out, which is the fundamental principle that describes how a queue operates. According to this principle, the element that enters the queue first will be the first one to come out of it. This means the element that has been in the queue for the longest time will be removed first.
This approach is also known as First Come First Served (FCFS). In a queue, new elements are always added at one end called the REAR, and elements are always removed from the other end called the FRONT. This arrangement ensures that elements are processed in the exact order they arrive.
Explanation
The textbook clearly explains FIFO in section 4.1.1, stating that queue follows this principle since 'the element entering first in the queue will be the first one to come out of it.' The context also mentions that FIFO is known as FCFS (First Come First Served) approach. The structural arrangement of queue—with REAR for insertion and FRONT for deletion—enforces this FIFO behavior.