LeetCode Plus One

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