queue operation using array

queue_array.cpp

#include<iostream>
#define _size 5
using namespace std;
class _queue{
	int front = -1;
	int rear = -1;
	int A[_size];
	public:
		void enqueue(int);
		int dequeue();
		void display();
};
void _queue :: enqueue(int item){
	if(rear == _size)
		cout<<"Overflow"<<endl;
	else{
		if(rear == -1 && front == -1)
			front = 0;

		rear += 1;
		A[rear] = item;
	}
}
int _queue :: dequeue(){
	int item;
	if(front == -1){
		cout<<"Empty"<<endl;
		exit(0);
	}
	else{
		item = A[front];
		if(front == rear){
			front = -1;
			rear = -1;
		}
		else
			front += 1;
	}
	return item;
}
void _queue :: display(){
	if(front == -1)
		cout<<"Empty"<<endl;
	else{
		cout<<"Items are -"<<endl;
		for(int i=front ; i<=rear ; i++){
			cout<<A[i]<<" ";
		}
		cout<<endl;
	}
}
int main(){
	_queue a;
	a.display();
	a.enqueue(10);
	a.enqueue(20);
	a.enqueue(30);
	a.display();
	cout<<"deleted item is: "<< a.dequeue()<<endl;
	cout<<"deleted item is: "<< a.dequeue()<<endl;
	cout<<"deleted item is: "<< a.dequeue()<<endl;
	cout<<"deleted item is: "<< a.dequeue()<<endl;
	a.display();
	return 0;
}
// this code is contribute by suvasish das.
// https://suvasish114.github.io/