#include <iostream> #include <map> #include <vector> using namespace std; int main(void) { int N; cin >> N; vector<string> a(N), b(N); map<string, int> mp; int ptr = 0; for(int i=0; i<N; ++i) { cin >> a[i] >> b[i]; if(!mp.count(a[i])) { mp[a[i]] = ptr++; } if(!mp.count(b[i])) { mp[b[i]] = ptr++; } } size_t n = mp.size(); vector<bool> seen(n); for(int i=0; i<N; ++i) { seen[mp[a[i]]] = true; } for(int i=0; i<N; ++i) { if(!seen[mp[b[i]]]) { cout << b[i] << '\n'; seen[mp[b[i]]] = true; } } return 0; }