题解 | #第一个只出现一次的字符# find_first_of和find_last_of

class Solution {
public:
    int FirstNotRepeatingChar(string str) {
        int len = str.size();
        for (int i = 0; i < len; i++) {
            if (str.find_first_of(str[i]) == str.find_last_of(str[i])) {
                return i;
            }
        }
        return -1;
        
    }
};