static int length(SinglyLinkedListNode temp)
     {
        int len =0;
        while(temp != null)
        {
            len++;
            temp = temp.next;
        }
        return len;
     }
    static int findMergeNode(SinglyLinkedListNode head1, SinglyLinkedListNode head2) {
        
        int len1 = length(head1);
        int len2 = length(head2);
        int mov = 0;
        SinglyLinkedListNode temp = null;
        boolean head1_moved = false;
        boolean head2_moved = false;
        if(len1 > len2)
        {
            mov = len1 - len2;
            temp = head1;
            while(mov-- > 0)
            {
                temp = temp.next;
            }
            head1_moved = true;
        }
        else if(len1 <= len2)
        {
            mov = len2 - len1;
            temp = head2;
            while(mov-- > 0)
            {
                temp = temp.next;
            }
            head2_moved = true;
        }
        
        if(head1_moved)
        {
            SinglyLinkedListNode curr = head2;
            while(temp != null)
            {
                if(curr == temp)
                {
                    return curr.data;
                }
                temp = temp.next;
                curr = curr.next;
            }
        }
        else if(head2_moved){
            SinglyLinkedListNode curr = head1;
            while(temp != null)
            {
                if(curr == temp)
                {
                    return curr.data;
                }
                temp = temp.next;
                curr = curr.next;
            }
        }
        
        
        return -1;

    }