func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n;     cin >> n;     int cnt[1001] = {0}, a[n];     for (int i = 0; i < n; ++i) {       cin >> a[i];       cnt[a[i]] = i;     }     int vis[1001] = {0};     vector<int> res;     for (int i = 0; i < n; i++) {       if (cnt[a[i]] == i) res.push_back(a[i]);     }     cout << res.size() << endl;     for (int i = 0; i < res.size(); ++i) cout << res[i] <<    ;     cout << endl;     return 0;   }   