public class CircularLinkedList {

class Node{

int data;

Node next;

Node(int data){

this.data=data;

this.next=null;

}

}

Node head=null;

Node tail=null;

public void addNode(int data) {

Node n=new Node(data);

if(head==null) {

head=n;

tail=n;

}

else {

tail.next=n;

tail=n;

tail.next=head;

}

}

void insertAtbeg(int data) {

Node n=new Node(data);

if(head==null) {

head=n;

tail=n;

}

Node temp=head;

head=n;

n.next=temp;

}

public void display() {

Node current=head;

if(head==null) {

System.out.println("List is Empty");

return;

}

else {

do {

System.out.print(current.data+",");

current=current.next;

}

while(current !=head);

System.out.println();

}

}

public static void main(String[] args) {

CircularLinkedList c1=new CircularLinkedList();

c1.addNode(10);

c1.addNode(20);

c1.addNode(30);

c1.addNode(40);

c1.display();

c1.insertAtbeg(100);

c1.display();

}

}