// UUID: 9a221d1d-8b12-44bd-8c37-f808e5915411
#include <bits/stdc++.h>
using namespace std;

bool vis[100001];
vector<vector<int>> v;
vector<int> dp;

void dfs(int q){
    vis[q] = true;
    for(int i : v[q]){
        dp[i] = dp[q] + 1;
        if(vis[i] == false) dfs(i);
    }
}


int main() {
    int n; cin >> n;
    v.resize(n + 1);
    dp.resize(n + 1);
    for(int j = 0; j < n; j++){
        int a, b; cin >> a >> b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    for(int j = 1; j <= n; j++){
        if(vis[j] == false){
            dfs(j);
        }
    }
    int legnagyobb = 0, index;
    for(int j = 1; j <= n; j++){
        if(legnagyobb < dp[j]){
            legnagyobb = dp[j];
            index = j;
        }
    }
    cout << index - 1;
}