#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int main() {
    int n;
    cin >> n;
    n--;
    vector<int> a[n+9];
    int w, u;
    string v[2];
    for (int i = 0; i < n+9; i++)
    {
        a[i] = vector<int>();
    }
    vector<int> fel;
    vector<int> le;
    for (int i = 0; i < n; i++)
    {
        cin >> v[0] >> v[1];
        w = stoi(v[0]);
        u = stoi(v[1]);
        fel.push_back(w);
        le.push_back(u);
        a[w].push_back(u);
    }
    fel.erase(set_difference(fel.begin(), fel.end(), le.begin(), le.end(), fel.begin()), fel.end());
    while (le.size() != 0)
    {
        fel.clear();
        fel.insert(fel.end(), le.begin(), le.end());
        le.clear();
        for (int i = 0; i < fel.size(); i++)
        {
            le.insert(le.end(), a[fel[i]].begin(), a[fel[i]].end());
        }
    }
    cout << fel[0] << endl;
    return 0;
}