func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int samples, len, temp, sz;     cin >> samples >> len;     deque<int> q;     set<int> s;     sz = s.size();     for (; samples--;) {       cin >> temp;       s.insert(temp);       if (s.size() > sz) {         q.push_front(temp);         if (q.size() > len) {           s.erase(q[q.size() - 1]);           q.pop_back();         }       }       sz = s.size();     }     printf( %d n , q.size());     for (auto x : q) printf( %d  , x);     return 0;   }   