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

const int MAXN = 100001;

vector<int> g[MAXN];
bool p[MAXN];
int ans = 1, best = 0;

void dfs(int u, int p, int d) {
	if (best < d) {
		best = d;
		ans = u;
	}
	for (int v : g[u])
		if (v != p)
			dfs(v, u, d+1);
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	
	int n;
	cin >> n;
	for (int i = 0; i < n-1; i++) {
		int a, b;
		cin >> a >> b;
		g[a].push_back(b);
		p[b] = true;
	}
	for (int i = 1; i <= n; i++) {
		if (!p[i]) dfs(i, 0, 0);
	}
	cout << ans << "\n";
}