What is a queue data structure in C++?

What is a queue data structure in C++?

A queue is a linear data structure that follows the First In First Out (FIFO) principle. In C++, it can be implemented using arrays or linked lists.

Can you show me how to implement a queue using an array?

Sure! Here's a simple implementation:

class Queue {
private:
    int front, rear, size;
    int* queue;
public:
    Queue(int s) {
        front = rear = 0;
        size = s;
        queue = new int[s];
    }
    void enqueue(int value) {
        if (rear == size) {
            std::cout << "Queue is full!";
            return;
        }
        queue[rear++] = value;
    }
    int dequeue() {
        if (front == rear) {
            std::cout << "Queue is empty!";
            return -1;
        }
        return queue[front++];
    }
};

This code defines a simple queue class with enqueue and dequeue methods.

What are the advantages of using a queue?

Queues are useful for managing tasks in a sequential order, such as scheduling processes in operating systems, handling requests in web servers, and more. They help in maintaining the order of execution.

Can you explain the difference between a queue and a stack?

Certainly! A queue follows the FIFO principle, meaning the first element added is the first to be removed. A stack, on the other hand, follows the Last In First Out (LIFO) principle, where the last element added is the first to be removed.