class Solution {
    public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
        ListNode list=new ListNode(0);
        ListNode current=list;
        int x=0;int y=0;
        int h=0;
        int r=0;
        while(l1!=null || l2!=null){
        if(l1!=null){
            x=l1.val;
            l1=l1.next;
        }
        else x=0;
         if(l2!=null){
            y=l2.val;
            l2=l2.next;
        }
        else y=0;
        int sum=x+y+h;
        r=sum%10;
        h=sum/10;
        current.next=new ListNode(r);
        current=current.next;     
       
    }
        if (h!=0){
            current.next=new ListNode(h);
        }
        return list.next;
    }
 
}