Add Two Numbers

问题描述:

Input:(2 -> 4 -> 3) + (5 -> 6 -> 4)
Output:7 -> 0 -> 8
Explanation:342 + 465 = 807.

代码:

/**
* 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 Nhead = new ListNode(0);   
  var head = Nhead;   
  var plus = 0;   
  while(l1 || l2 || plus) {       
    var temp = plus;       
    if(l1!=null){           
    temp += l1.val;           
    l1 = l1.next;       
}       
if(l2!=null){           
  temp += l2.val;           
  l2 = l2.next;       
}
  plus = parseInt(temp/10);       
  head.next = new ListNode(temp%10);//head值变了, Nhead也变了       
  head = head.next; //head指向了下一个节点 但是Nhead没变
}   
  return Nhead.next;
};