66. Plus One

题目地址

注意当输入为空时应该输出1.

class Solution {public:    vector<int> plusOne(vector<int> &digits) {        reverse(digits.begin(), digits.end());        vector<int> ans;        int carry = 0;        for (int i = 0; i < digits.size(); ++i) {            int plus = i == 0 ? 1 : 0;            int now = (plus + digits[i] + carry) % 10;            carry = (plus + digits[i] + carry) / 10;            ans.push_back(now);        }        if (carry) ans.push_back(carry);        reverse(ans.begin(), ans.end());        if (ans.size() == 0) ans.push_back(1);        return ans;    }};