Circular_Queue_operations.cpp

#include<iostream>
using namespace std;
#define SIZE 5
class CircularQueue{
	int arr[SIZE];
	int front, rear, count;
public:
	CircularQueue(){
		front = 0;
		rear = -1;
		count = 0;
	}
	bool isfull(){
		return (count == SIZE);
	}
	bool isempty(){
		return (count == 0);
	}
	void enqueue(int x){
		if(isfull()){
			cout<<"full!"<<endl;
			return;
		}
		rear = (rear + 1) % SIZE;
		arr[rear]=x;
		count++;
	}
	void dequeue(){
		if(isempty()){
			cout<<"Empty!"<<endl;
			return;
		}
		cout<<arr[front]<<" removed."<<endl;
		front = (front + 1) % SIZE;
		count--;
	}
	int peek(){
		if(isempty()){
			cout<<"Empty!"<<endl;
			return -1;
		}
		return arr[front];
	}
	int getRear(){
		if(isempty()){
			cout<<"Empty."<<endl;
			return -1;
		}
		return arr[rear];
	}
	void display(){
		if(isempty()){
			cout<<"Empty!"<<endl;
			return;
		} else {
			for(int i=0; i<count; i++){
				cout<<arr[(front + i) % SIZE] <<" ";
			}
			cout<<endl;
		}
	}
};
int main(){
	CircularQueue q;
	q.enqueue(10);
	q.enqueue(20);
	q.enqueue(30);
	q.display();
	
	q.dequeue();
	q.enqueue(40);
	q.enqueue(50);
	q.display();
	
	q.enqueue(60);
	q.display();
	
	cout<<"Front= "<<q.peek()<<", Rear="<<q.getRear()<<endl;
	return 0;
}