#include <bits/stdc++.h>
using namespace std;
vector<int> g[100001];
int bfs(int x){
	pair<int, int> mx={0,0};
	queue<int> q;
	int t[100001];
	q.push(x);
	while (!q.empty()){
		int v=q.front();
		q.pop(); 
		for (int edge:g[v]){
			t[edge]=t[v]+1;
			if (t[edge]>mx.first) mx={t[edge],edge};
			q.push(edge);
		}
	}
	return mx.second;
}
int main() {
	int n;
	cin>>n;
	vector<int> c(n+1);
	for (int i=1; i<n;i++){
		int x,y;
		cin>>x>>y;
		c[y]++;
		g[x].push_back(y); 
	}
	for (int i=1; i<=n;i++){
		if (c[i]==0) {
			cout<<bfs(i);
			return 0; 
		}
	}
}