#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <cmath>
#include <queue>
#include <map>
#include <unordered_map>
#include <set>
#include <functional>
#include <bitset>
#include <cassert>
#include <random>
#include <iterator>
using namespace std;
using ll = long long;


int main() {
	int n; cin >> n;
	vector<string> v(n);
	set<string> s, t;
	for (int i = 0; i < n; i++) {
		string a; cin >> a >> v[i];
		s.insert(v[i]);
		t.insert(a);
	}
	set<string> diff;
	set_difference(
		s.begin(), s.end(),
		t.begin(), t.end(),
		inserter(diff, diff.begin()));
	for (const auto& a : v) {
		if (diff.count(a)) {
			cout << a << endl;
			diff.erase(a);
		}
	}
	return 0;
}