#include<bits/stdc++.h>
using namespace std;
vector<int> G[30007];
bool w[30007];
int odl[30007], maks = 0;
void DFS(int a, int d){
  w[a] = 1;
  odl[a] = d;
  maks = max(maks, d);
  for(int i = 0;i < G[a].size();i++)
    if(!w[G[a][i]])
      DFS(G[a][i], d + 1);
}
int main(){
  int n;
  cin >> n;
  for(int i = 1, a, b;i < n;i++){
    cin >> a >> b;
    G[a].push_back(b);
    G[b].push_back(a);
  }
  for(int i = 1;i <= n;i++){
    for(int j = 1;j <= n;j++)
      w[j] = 0;
    DFS(i, 0);
  }
  cout << maks;
}