#include #include #include using namespace std; int main() { ios::sync_with_stdio(false); cin.tie(0); int n; string s; set bad; vector good; cin >> n; while (n--) { cin >> s; bad.insert(s); cin >> s; good.push_back(s); } for (string i : good) if (bad.find(i) == bad.end()) { cout << i << endl; bad.insert(i); } }