31 char s[100];32 33 int main() {34     strcpy(s, "123");35     cout << atoi(s) << endl;    //atol同atoi36 37     strcpy(s, "12.3");38     cout << atof(s) << endl;    //没有atolf39     40     strcpy(s, "12345678987654321");41     cout << atoll(s) << endl;42 43     return 0;44 }