#include #define int long long using namespace std; const int MOD = 1000000007; signed main() { int N; cin >> N; set A; vector B(N); for( int i = 0; i < N; i++ ){ string a; cin >> a >> B.at(i); A.insert(a); } set ans; for( int i = 0; i < N; i++ ){ if( A.count(B.at(i)) ) continue; else{ if( ans.count(B.at(i)) ) continue; else{ cout << B.at(i) << endl; ans.insert(B.at(i)); } } } }