#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
int main() {
    int N;
    cin >> N;
    string A[N], B[N];
    set<string> g;
    for (int i = 0; i < N; i++) {
        cin >> A[i] >> B[i];
        g.insert(A[i]);
    }
    set<string> f;
    vector<string> p;
    for (string s : B) {
        if (g.count(s) == 0 && f.count(s) == 0) {
            p.push_back(s);
            f.insert(s);
        }
    }
    for (string s : p) {
        cout << s << "\n";
    }
    return 0;
}