func_code_string: #include <bits/stdc++.h>   using namespace std;   void reverseQueue(queue<long long int>& q) {     if (q.empty()) return;     long long int data = q.front();     q.pop();     reverseQueue(q);     q.push(data);   }   int main() {     ios_base::sync_with_stdio(0);     int n, k;     cin >> n >> k;     vector<long long int> friends;     queue<long long int> q;     map<long long int, int> check;     for (int i = 0, temp; i < n; i++) {       cin >> temp;       friends.emplace_back(temp);       if (i < k) {         if (check.find(friends[i]) == check.end() || check[friends[i]] == 0) {           q.push(temp);           check[temp] = 1;         }       }     }     for (int i = k; i < n; i++) {       if (check.find(friends[i]) == check.end() || check[friends[i]] == 0) {         if (q.size() == k) {           check[q.front()] = 0;           q.pop();         }         q.push(friends[i]);         check[friends[i]] = 1;       }     }     reverseQueue(q);     cout << q.size() << endl;     while (!q.empty()) {       cout << q.front() <<    ;       q.pop();     }     cout << endl;     return 0;   }   