Linear_Queue_Task_4.cpp

#include<iostream>
using namespace std;
#define SIZE 5
    class LinearQueue {
    	int arr[SIZE];
    	int front, rear;
    public:
    	LinearQueue(){
    		front = -1;
    		rear = -1;
		}
		bool isEmpty(){
			return (front==-1 && rear==-1);
		}
		bool isFull(){
			return (rear == SIZE - 1);
		}
		void enqueue(int x) {
			if(isFull()){
				cout<<"Queue is full "<<endl;
				return;
			}
			if (isEmpty()){
				front = 0;
			}
			rear++;
			arr[rear]=x;
			cout<<x<<" inserted"<<endl;
		}
		void dequeue(){
			if(isEmpty()){
				cout<<"Queue is empty."<<endl;
				return;
			}
			cout<<arr[front]<<" removed "<<endl;
			if(front==rear){
				front = rear = -1;
			} else {
				front++;
			}
		}
		int peek(){
			if(isEmpty()){
				cout<<"Queue is empty."<<endl;
				return -1;
		} 
		return arr[front];
	}
		int getRear(){
		  if(isEmpty()){
		  	cout<<"Queue is empty."<<endl;
		  	return -1;
		  }	
		  return arr[rear];
		}
		void display(){
			if(isEmpty()){
				cout<<"Queue is empty."<<endl;
				return;
			}
			cout<<"Queue elements: ";
			for(int i=front; i<=rear; i++){
				cout<<arr[i]<<" ";
			}
			cout<<endl;
		}
	};
	int main(){
		LinearQueue q;
		q.enqueue(10);
		q.enqueue(20);
		q.enqueue(30);
		
		q.display();
		
		cout<<"Front Element: "<<q.peek()<<endl;
		cout<<"Rear element: "<<q.getRear()<<endl;
		
		q.dequeue();
		q.display();
		
		q.enqueue(40);
		q.enqueue(50);
		q.enqueue(60);
		
		q.display();
		return 0;
}