#include <iostream>
#include <vector>
using namespace std;

vector<vector<int>> graph;
int m=0;
vector<bool> visit;
int ans;
void dfs(int s,int dist)
{
visit[s]=true;
if(dist>m)
    {
    m=dist;
    ans=s;
    }
for(auto x : graph[s])
    {
    if(!visit[x])
        dfs(x,dist+1);
    }
}



int main()
{
    int n;
    cin>>n;
    graph.resize(n+1);
    visit.resize(n+1);
    int x,y;
    vector<int> indeg(n+1,0);
    for(int i=0;i<n-1;i++)
        {
        cin>>x>>y;
        graph[x].push_back(y);
        indeg[y]++;
        }
    for(int i=1;i<=n;i++)
        {
        if(!indeg[i])
            {
            dfs(i,1);
            cout<<ans;
            return 0;
            }
        }
    return 0;
}