func_code_string: #include <bits/stdc++.h>   using namespace std;   long long freq[100005];   int32_t main() {     long long n;     cin >> n;     string s;     cin >> s;     sort(s.begin(), s.end());     reverse(s.begin(), s.end());     cout << s[0];     for (long long i = 1; i < n; i++) {       if (s[i] ==  0 ) cout << s[i];     }     return 0;   }   