#include <bits/stdc++.h>
using namespace std;

int main() {
  ios::sync_with_stdio(false);

  int N;
  cin >> N;

  vector<string> A(N), B(N);
  for (int i = 0; i < N; ++i) {
    cin >> A[i] >> B[i];
  }

  vector<string> names;
  set<string> known;
  set<string> cheat;
  for (int i = 0; i < N; ++i) {
    if (!known.count(B[i])) names.push_back(B[i]);
    known.insert(B[i]);
    cheat.insert(A[i]);
  }

  for (string name : names) {
    if (cheat.count(name)) continue;
    cout << name << endl;
  }

  return 0;
}