//url:https://leetcode.com/problems/to-lower-case/description/
//其实就是找出大写字母，然后换为小写就可以了
class Solution {
public:
    string toLowerCase(string str) {
        string result=str;
        for(int i=0;i='A'&&result[i]<='Z')
                result[i]=result[i]+32;
        }
        return result;
    }
};