LeetCode-2. Add Two Numbers

Add Two Numbers

You are given two non-empty linked lists representing two non-negative integers. 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.

You may assume the two numbers do not contain any leading zero, except the number 0 itself.

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

/** * Definition for singly-linked list. * function ListNode(val) { *     this.val = val; *     this.next = null; * } *//** * @param {ListNode} l1 * @param {ListNode} l2 * @return {ListNode} */var addTwoNumbers = function(l1, l2) {    var sum=l1.val+l2.val;    var nxt1=l1.next,nxt2=l2.next;    var l3=new ListNode(sum%10);    var p=l3;    var carry=Math.floor(sum/10);    while(nxt1||nxt2||carry!==0){        sum=carry+(nxt1?nxt1.val:0)+(nxt2?nxt2.val:0);        p.next=new ListNode(sum%10);        p=p.next;        nxt1=nxt1?nxt1.next:null;        nxt2=nxt2?nxt2.next:null;        carry=Math.floor(sum/10);    }    return l3;};