/**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode() {}
* ListNode(int val) { this.val = val; }
* ListNode(int val, ListNode next) { this.val = val; this.next = next; }
* }
*/
class Solution {
public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
boolean isAdd = false;
ListNode current = new ListNode();
ListNode result = current;
while (l1 != null || l2 != null || isAdd) {
if (l1 == null) {
l1 = new ListNode();
}
if (l2 == null) {
l2 = new ListNode();
}
int sum = l1.val + l2.val;
if (isAdd) {
sum = sum + 1;
isAdd = false;
}
if (sum >= 10) {
isAdd = true;
sum = sum - 10;
}
current.val = sum;
if (l1.next != null || l2.next != null || isAdd) {
current.next = new ListNode();
current = current.next;
}
l1 = l1.next;
l2 = l2.next;
};
return result;
}
}