func_code_string: #include <bits/stdc++.h>   using namespace std;   string input;   int main() {     cin >> input;     int last = -1;     for (char i =  z ; i >=  a ; i--)       for (int j = last + 1; j < input.length(); j++)         if (input[j] == i) {           cout << input[j];           last = j;         }     return 0;   }   