Add Two Numbers

Add Two Numbers

/**

 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) { val = x; }
 * }
 */

class Solution {
    public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
        if(l2==null){
            return l1;
        }
        if(l1==null){
            return l2;
        }
        ListNode newhead=new ListNode(-1);
        ListNode l3=newhead;
        int carry=0;
        while(l1!=null||l2!=null){
            if(l1!=null){
                carry=carry+l1.val;
                l1=l1.next;
            }
            if(l2!=null){
                carry=carry+l2.val;
                l2=l2.next;
            }
            l3.next=new ListNode(carry%10);
            carry=carry/10;
            l3=l3.next;
        }
        if(carry==1){
            l3.next=new ListNode(1);
         
        }
        return newhead.next;
    }
}