#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream in ("darb.in");
ofstream out ("darb.out");

const int NMax = 1e5 + 2;
int N, Dist[NMax], Maxim;
vector <int> G[NMax];
queue <int> Q;

void Citire (){
    in >> N;
    for (int i = 1; i < N; i++){
        int x, y;
        in >> x >> y;
        G[x].push_back (y);
        G[y].push_back (x);
    }
}

void BFS(int Nod){
    for (int i = 1; i <= N; i++)
        Dist[i] = 0;
    Dist[Nod] = 1;
    Q.push(Nod);
    while (!Q.empty()){
        int Node = Q.front();
        Q.pop();
        for (int i : G[Node])
            if (Dist[i] == 0){
                Dist[i] = Dist[Node] + 1;
                Q.push(i);
                if (Dist[i] > Maxim)
                    Maxim = Dist[i];
            }
    }
}

int main(){
    Citire();
    for (int i = 1; i <= N; i++){
        if (G[i].size() == 1){
            BFS(i);
        }
    }
    out << Maxim;
    return 0;
}