public class p32_circularQ {
    public static void main(String[] args) {
        Queue q=new Queue(5);
        q.add(0);
        q.add(1);
        q.add(2);
        q.delete();
        q.add(4);
        
      
        while(!q.isEmpty()){
            System.out.println(q.peek());
            q.delete();
        }

    }

    static class Queue {
        static int arr[];
        static int size;
        static int rear;
        static int front;

        Queue(int n) {
            arr = new int[n];
            size = n;
            rear = -1;
            front=-1;
        }

        public static boolean isEmpty() {
            return rear == -1 && front==-1;
            // if(rear==-1){
            // return true;
            // }
            // return false;
        }

        public static boolean isFull(){
            return (rear+1)%size==front;
        }

        public static int delete() {
            if (rear == -1) {
                System.out.println("Empty");
                return -1;
            } 
                int temp = arr[0];
                if(rear==front){
                    rear=front=-1;
                }else{
                front=(front+1)%size;
                }
                return temp;
            
        }

        public static void add(int data) {
            if (isFull()) {
                System.out.println("Queue is full");
                return;
            } //add 1st ele
                if(front==-1){
                    front=0;
                }
                rear = (rear + 1)%size;
                arr[rear] = data;
            
        }

        public static int peek() {
            if (rear == -1) {
                System.out.println("Empty");
                return -1;
            }

            return arr[front];

        }

    }
}