LeetCode 2.两数之和

题目思路
类似于大数加法的思路，只不过每次操作的时候是用链表的节点
实现代码

class Solution {
public:
    ListNode* addTwoNumbers(ListNode* l1, ListNode* l2) {
        auto dummy = new ListNode(-1), cur = dummy;
        int t = 0;
        while(l1 || l2 || t)
        {
            if(l1) t += l1->val, l1 = l1->next;
            if(l2) t += l2->val, l2 = l2->next;
            cur = cur->next = new ListNode(t % 10);
            t /= 10;
        }
        return dummy->next;
    }
};