[LeetCode][JavaScript]Add Two Numbers

Add Two Numbers

You are given two linked lists representing two non-negative numbers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.

Input: (2 -> 4 -> 3) + (5 -> 6 -> 4)
Output: 7 -> 0 -> 8

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

链表储存的大数加法。

 1 /**
 2  * Definition for singly-linked list.
 3  * function ListNode(val) {
 4  *     this.val = val;
 5  *     this.next = null;
 6  * }
 7  */
 8 /**
 9  * @param {ListNode} l1
10  * @param {ListNode} l2
11  * @return {ListNode}
12  */
13 var addTwoNumbers = function(l1, l2) {
14     var carry = 0;
15     var result = new ListNode(-1);
16     var resHead = result;
17     while(l1 !== null || l2 !== null){
18         var sum = carry;
19         if(l1 !== null){
20             sum += l1.val;
21             l1 = l1.next;
22         }
23         if(l2 !== null){
24             sum += l2.val;
25             l2 = l2.next;
26         }
27 
28         var node = null;
29         if(sum >= 10){
30             node = new ListNode(sum - 10);
31             carry = 1;
32         }else{
33             node = new ListNode(sum);
34             carry = 0;
35         }
36         result.next = node;
37         result = result.next;
38     }
39     if(carry === 1){
40         result.next = new ListNode(1);
41     }
42     return resHead.next;
43 };