每日leetcode-Add Two Numbers

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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

感觉这个题目的理解有点问题啊！上述红字的部分难道不是说链表的每个节点的存储顺序是逆序的，然后实际上就是逆序相加并且记录进位？

自己实际测试的时候仍然得到的结果是顺序的。。。。

实现代码

/**
 * 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) {
        
        
        ListNode* p = new ListNode(0);
        ListNode* head=p;
        int cn = 0;

        while(l1 || l2) {
            int val = cn + (l1 ? l1->val : 0) + (l2 ? l2->val : 0);
            cn = val / 10;
            val = val % 10;
            p->next = new ListNode(val);
            p = p->next;
            if(l1) {
                l1 = l1->next;
            }
            if(l2) {
                l2 = l2->next;
            }
        }

        if(cn != 0) {
            p->next = new ListNode(cn);
            p = p->next;
        }

        return head->next;  
        
    }
};