[LeetCode]2. Add Two Numbers

https://leetcode.com/problems/add-two-numbers/

链表代表一个数，两个链表求和。

解法很简答，看看这种最concise的code

/** * Definition for singly-linked list. * public class ListNode { *     int val; *     ListNode next; *     ListNode(int x) { val = x; } * } */public class Solution {    public ListNode addTwoNumbers(ListNode l1, ListNode l2) {        int add = 0;        ListNode head = new ListNode(0);        ListNode cur = head;        while (l1 != null || l2 != null) {            int sum = add;            if (l1 != null) {                sum += l1.val;                l1 = l1.next;            }            if (l2 != null) {                sum += l2.val;                l2 = l2.next;            }            cur.next = new ListNode(sum % 10);            add = sum / 10;            cur = cur.next;        }        if (add != 0) {            cur.next = new ListNode(1);        }        return head.next;    }}