LeetCode 2 Add Two Number

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

摘要： 翻译： 给你两个表示两个非负数字的链表。数字以相反的顺序存储，其节点包含单个数字。将这两个数字相加并将其作为一个链表返回。 输入: (2 -> 4 -> 3) + (5 -> 6 -> 4) 输出: 7 -> 0 -> 8

C++:

/**
* Definition for singly-linked list.
* struct ListNode {
*     int val;
*     ListNode *next;
*     ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution{
public:
ListNode *addTwoNumbers(ListNode* l1, ListNode* l2){
int sum = 0;
ListNode *listNode = new ListNode(0);
ListNode *p1=l1, *p2=l2, *p3=listNode;
while(p1!=NULL||p2!=NULL)
{
if(p1!=NULL)
{
sum+=p1->val;
p1=p1->next;
}
if(p2!=NULL)
{
sum+=p2->val;
p2=p2->next;
}
p3->next=new ListNode(sum%10);
p3=p3->next;
sum=sum/10;
}
if(sum==1)
{
p3->next=new ListNode(1);
}
return listNode->next;
}
};