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 arrays?

Sure! Here's a simple implementation of a queue using an array in C++:

#include <iostream>
#define MAX 100

class Queue {
    int front, rear;
    int arr[MAX];

public:
    Queue() { front = rear = -1; }

    void enqueue(int x) {
        if (rear == MAX - 1) {
            std::cout << "Queue is full!";
            return;
        }
        if (front == -1) front = 0;
        arr[++rear] = x;
    }

    void dequeue() {
        if (front == -1 || front > rear) {
            std::cout << "Queue is empty!";
            return;
        }
        front++;
    }

    void display() {
        if (front == -1 || front > rear) {
            std::cout << "Queue is empty!";
            return;
        }
        for (int i = front; i <= rear; i++) {
            std::cout << arr[i] << " ";
        }
        std::cout << std::endl;
    }
};

This code defines a simple queue with enqueue, dequeue, and display functions.

What are the advantages of using a queue?

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