leetcode | 面试题58 - II. 左旋转字符串

class Solution {
public:
    string reverseLeftWords(string s, int n) {
        string str = s + s;
        string res;
        for(int i = n; i < s.size() + n; i++)
        {
            res += str[i];
        }
        return res;
    }
};