func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     cout.tie(NULL);     string s;     char big =  a ;     string s1 =   ;     cin >> s;     for (int i = s.size() - 1; i >= 0; i--) {       if (int(s[i]) >= int(big)) {         s1 += s[i];         big = s[i];       }     }     reverse(s1.begin(), s1.end());     cout << s1;     return 0;   }   