02.md

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 = t / 10;
        }
        return dummy->next;
    }
};

注意点：

cpp中对象的属性 是用 -> 来找的 比如:

auto p1 = head
p1 = p1->next
xxx....