public static SinglyLinkedListNode insertNodeAtPosition(SinglyLinkedListNode llist, int data, int position) {
        SinglyLinkedListNode head = llist;
        SinglyLinkedListNode current = llist;
        SinglyLinkedListNode prevNode = null;
        int count = 0;
        while (current != null) {
            if (count == position) {
                SinglyLinkedListNode insNode = new SinglyLinkedListNode(data);
                insNode.next = current;
                if (prevNode == null) head = insNode;
                else prevNode.next = insNode;
                break;
            }
            prevNode = current;
            current = current.next;
            count++;
        }
        return head;
    }