Use 2 pointer approach, one pointer starting from 2 nodes ahead, if the two pointers meet at some point, list is circular

No

No

A linked list is called circular if it is not NULL-terminated and all nodes are connected in the form of a cycle. or an empty linked list is a circular. example inn java static boolean isCircular( Node head) { if (head == null) //empty linked list return true; Node node = head.next; //next head while (node != null && node != head) node = node.next; return (node == head);//loop stopped because of circular } static Node newNode(int data) { Node temp = new Node(); temp.data = data; temp.next = null; return temp; } public static void main(String args[]) { Node head = newNode(1); head.next = newNode(2); head.next.next = newNode(3); head.next.next.next = newNode(4); System.out.print(isCircular(head)? "Yes\n" : "No\n" ); // Making linked list circular head.next.next.next.next = head; System.out.print(isCircular(head)? "Yes\n" : "No\n" ); }