func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     string s, s1, s2;     cin >> s;     s1 = s;     sort(s1.begin(), s1.end());     s2 += s1[0];     for (int i = 1; i < s1.length(); i++) {       if (s1[i] != s1[i - 1]) s2 += s1[i];     }     int d = 0;     for (int j = s2.length() - 1; j >= 0; j--) {       for (int i = d; i < s.length(); i++) {         if (s2[j] == s[i]) cout << s[i], d = i + 1;       }     }     cout << endl;     return 0;   }   