func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n, k;     cin >> n >> k;     int arr[200007];     map<int, bool> vis;     queue<int> q;     for (int i = 1; i <= n; i++) {       cin >> arr[i];       if (vis[arr[i]]) continue;       vis[arr[i]] = true;       if (q.size() == k) {         vis[q.front()] = false;         q.pop();       }       q.push(arr[i]);     }     vector<int> v;     while (!q.empty()) {       v.push_back(q.front());       q.pop();     }     cout << (int)v.size() << endl;     for (int i = (int)v.size() - 1; i >= 0; i--) {       cout << v[i] <<    ;     }     cout << endl;     return 0;   }   