Question

When an element is added to a queue, where is it added?

Short answer

Question: Explain the process of adding an element to a queue and where the element is added. Answer: When an element is added to a queue, it is added at the back (rear) of the queue, following the First In, First Out (FIFO) principle. This process is called the enqueue operation. After adding the element, the rear pointer is updated to point to the newly added element. If the queue was empty before the enqueue operation, the front pointer is also updated to point to the new element.

Step-by-step solution

Introduction

A queue is a data structure that works on the First In, First Out (FIFO) principle. This means that the element that is added first will be removed first. In a queue, elements are added at the back (called rear) and removed from the front (called front).

Enqueue operation

When an element is added to a queue, it is added to the back of the queue. This process is called the enqueue operation. To perform this operation, we need to maintain a pointer called rear pointing to the last element of the queue.

Update pointers

After an element is added, we need to update the rear pointer to point to the newly added element. Also, if the queue was empty before the enqueue operation, we have to update the front pointer to point to the new element as well.

Enqueue operation example

Let's consider the following example, where we enqueue elements A, B, and C to an empty queue Q. 1. Enqueue element A: * The element A is added at the rear of the empty queue Q. * Both front and rear pointers are updated to point to element A. 2. Enqueue element B: * The element B is added at the rear of the queue Q, after element A. * The rear pointer is updated to point to element B. 3. Enqueue element C: * The element C is added at the rear of the queue Q, after element B. * The rear pointer is updated to point to element C. After these operations, the queue Q looks like this: Front (A) -> B -> C (Rear)

Conclusion

When an element is added to a queue, it is added at the back (rear) of the queue, following the First In, First Out (FIFO) principle. The pointers front and rear are updated accordingly to maintain the correct order of elements in the queue.