LeetCode Add Two Numbers-javascript 实现

题目链接：https://leetcode.com/problems/add-two-numbers/

题目描述：简单的链表题目；

Notes: 将javascript对象o赋值给变量a，变量a指向的是o的内存，即对a的修改就是对o的修改。

/**
 * Definition for singly-linked list.
 * function ListNode(val) {
 *     this.val = val;
 *     this.next = null;
 * }
 */
/**
 * @param {ListNode} l1
 * @param {ListNode} l2
 * @return {ListNode}
 */
function listLen(list){ //判断链表长度
    var len=0;
    while(list!=null){
        len++;
        list=list.next;
    }
    return len;
}

var addTwoNumbers = function(l1, l2) {
    let len1=listLen(l1);
    let len2=listLen(l2);
    if(len2>len1){
        let tmp=l1;
        l1=l2;
        l2=tmp;
    }
    let l3=l1;//暂存l1链表头
    while(l2!=null){
        let add=l1.val+l2.val;
        let carry=parseInt(add/10);
        add=add%10;
        l1.val=add;//做加法
        
        let tmpList=l1;
        while(carry>0){//进位
            if(tmpList.next==null){tmpList.next=new ListNode(0);}
            tmpList=tmpList.next;
            let add2=tmpList.val+carry;
            carry=parseInt(add2/10);
            add2=add2%10;
            tmpList.val=add2;
        }
        l1=l1.next;
        l2=l2.next;
    }
    return l3;
};