# What Kind of Data Structure Does a Queue Is?

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Heather Bennett

What Kind of Data Structure Does a Queue Is?

A queue is a linear data structure that follows the FIFO (First-In-First-Out) principle. It is similar to a real-life queue, where the first person who enters the line is the first one to be served.

In programming, a queue stores elements in such a way that the first element added is always the first one to be removed.

## Operations on a Queue

There are two main operations performed on a queue:

• Enqueue: This operation adds an element to the end of the queue. The newly added element becomes the last element.
• Dequeue: This operation removes an element from the front of the queue. The previously second element becomes the new front.

These operations make queues highly useful in scenarios where elements need to be processed in order and at specific times.

## Implementing a Queue

Queues can be implemented using various data structures, but two commonly used ones are arrays and linked lists.

### Array-based Implementation:

In an array-based implementation, we use an array to store elements of the queue. We maintain two pointers: one pointing to the front of the queue (the index from which elements are dequeued) and another pointing to the end of the queue (the index at which elements are enqueued).

To enqueue an element, we add it at the end of the array and update our rear pointer. To dequeue an element, we remove it from the front of the array and update our front pointer.

In a linked list-based implementation, we use a linked list to store elements of the queue. Each node in the linked list contains the element and a pointer to the next node.

We maintain two pointers: one pointing to the front of the queue (the head of the linked list) and another pointing to the end of the queue (the tail of the linked list).

To enqueue an element, we create a new node at the end of the linked list and update our tail pointer. To dequeue an element, we remove the node from the front of the linked list and update our head pointer.

## Conclusion

In conclusion, a queue is a data structure that follows the FIFO principle, making it suitable for scenarios where elements need to be processed in order. It can be implemented using arrays or linked lists, depending on specific requirements.

Understanding queues and their implementation is crucial for efficient problem-solving in various programming scenarios.