066. Plus One.cpp

class Solution {
public:
    vector<int> plusOne(vector<int>& digits) {
        int i = digits.size() - 1;
        while(i >= 0 && digits[i] == 9) digits[i--] = 0;
        if(i < 0) digits.push_back(0), i++;
        digits[i]++;
        return digits;
    }
};