#include <bits/stdc++.h>
#define NMax 100005
using namespace std;

ifstream fin("darb.in");
ofstream fout("darb.out");
int n, ap[NMax], T[NMax], nr;
vector <int> G[NMax];
queue <int> q;
pair <int, int> ramura[NMax];
void BFS(int start){
    q.push(start);
    T[start] = start;
    ap[start] = 1;
    while(!q.empty())
    {
        int nod = q.front();
        q.pop();
        for(int i = 0; i < G[nod].size(); i++)
        {
            int vecin = G[nod][i];
            if(!ap[vecin])
            {
                ap[vecin] = 1;
                q.push(vecin);
                T[vecin] = nod;
            }
        }
    }
}
int nr_root(int i){
    while(T[T[i]] != T[i])
    {
        i = T[i];
        nr++;
    }
    return i;
}
int main(){
    fin >> n;
    while(true)
    {
        if(fin.eof()) break;
        int x, y;
        fin >> x >> y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    BFS(1);
    int Max = 0;
    for(int i = 1; i <= n; i++)
    {
        nr = 1;
        int root = nr_root(i);
        ramura[i].first = nr;
        ramura[i].second = root;
    }
    int t = 1;
    for(int i = 2; i < n; i++)
        if(ramura[i].second != ramura[i+1].second) t = 0;
    sort(ramura+1, ramura+n+1);
    if(t == 0)
    {
        int dist1 = ramura[n].first;
        int ramura1 = ramura[n].second;
        int nr_total = 0;
        for(int i = n-1; i >= 1; i--)
        {
            int dist2 = ramura[i].first;
            int ramura2 = ramura[i].second;
            if(ramura1 != ramura2)
            {
                nr_total = dist1 + dist2;
                break;
            }
        }
        fout << nr_total + 1;
    }
    if(t == 1)
        fout << ramura[n].first + 1;
}