Queue: How is the "First-In-First-Out" of Queues Implemented? A Simple Example to Illustrate

A queue is a data structure that follows the "First-In-First-Out" (FIFO) principle. It only allows insertion at the rear and deletion at the front. Key concepts include the front (earliest element) and the rear (latest element), with basic operations being Enqueue (insertion) and Dequeue (deletion). In array-based implementation, a queue requires a front pointer, a rear pointer, and a fixed-capacity array. The queue is empty when front == rear, and full when rear == max_size. During Enqueue, the rear pointer is moved forward to store the new element; during Dequeue, the front pointer is moved forward to retrieve the element. Example Demonstration: For a queue with capacity 5, initially front=0 and rear=0. After enqueuing 1, 2, 3, rear becomes 3, with the queue elements [1, 2, 3]. Dequeuing 1 makes front=1, and enqueuing 4 moves rear to 4. Enqueuing 5 results in a full queue. Dequeuing 2 (front=2) leaves the final queue as [3, 4, 5]. Applications include task scheduling, Breadth-First Search (BFS), printer queues, and network request handling, playing a critical role in data processing and task queuing scenarios.