[LeetCode] Plus One

Given a number represented as an array of digits, plus one to the number.

进位和加法。

class Solution {
public:
    vector<int> plusOne(vector<int> &digits) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        vector<int> ret(digits);
        reverse(ret.begin(), ret.end());
        
        int flag = 1;
        for(int i = 0; i < ret.size(); i++)
        {
            ret[i] += flag;
            flag = ret[i] / 10;
            ret[i] %= 10; 
        }
        
        if (flag == 1)
            ret.push_back(1);
        
        reverse(ret.begin(), ret.end());
        
        return ret;
    }
};