func_code_string: #include <bits/stdc++.h>   using namespace std;   const int MAX = 1e5 + 5;   int n;   char a[MAX];   pair<char, int> b[MAX];   int main() {     cin >> (a + 1);     n = strlen(a + 1);     for (int i = 1; i <= n; ++i) {       b[i].first = a[i];       b[i].second = i;     }     sort(b + 1, b + n + 1,          [&](const pair<char, int> &a, const pair<char, int> &b) {            if (a.first == b.first) {              return a.second < b.second;            }            return a.first > b.first;          });     for (int i = 1, j = 0; i <= n; ++i) {       if (j < b[i].second) {         cout << b[i].first;         j = b[i].second;       }     }     cout <<   n ;   }   