#include <bits/stdc++.h>

using namespace std;

using ll = long long;

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    int n;
    cin >> n;
    vector<string> b(n);
    set<string> ban;
    for (int i = 0; i < n; i++) {
        string a;
        cin >> a >> b[i];
        ban.insert(a);
    }

    set<string> used;
    for (int i = 0; i < n; i++) {
        if (used.count(b[i])) continue;
        used.insert(b[i]);
        if (ban.count(b[i])) continue;
        cout << b[i] << "\n";
    }
    return 0;
}