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

int main(void) {
  int N;
  cin >> N;
  map<string, bool> ans;
  vector<string> A(N), B(N);
  set<string> outputed;
  for (int i = 0; i < N; i++) {
    cin >> A[i] >> B[i];
  }

  for (int i = 0; i < N; i++) {
    ans[B[i]] = true;
  }

  for (int i = 0; i < N; i++) {
    ans[A[i]] = false;
  }

  for (int i = 0; i < N; i++) {
    if (ans[B[i]] && outputed.find(B[i]) == outputed.end()) {
      cout << B[i] << endl;
      outputed.insert(B[i]);
    }
  }
  return 0;
}