141. Linked List Cycle

class HasCycleInLinkedList{
   public boolean hasCycle(ListNode head){
       if(head == null || head.next == null) return false;
       if(head.next == head) return true; ListNode nextNode = head.next;
       head.next = head;
       boolean isCycle = hasCycle(nextNode);
       return isCycle;
   }
}