#include <iostream>
#include <vector>
#include <set>
#include <algorithm>
using namespace std;
int n,ans = 1e9;
vector<int> g[200001];
int kids[200001];
multiset<int> si,so;
void DFS(int u,int p = -1){
kids[u] = 1;
for(auto v : g[u]) if(v != p){
DFS(v,u);
kids[u] += kids[v];
}
}
inline void calc(int x,int y,int z){
ans = min(ans,max({abs(x-y),abs(y-z),abs(x-z)}));
}
void solve(int u,int p = -1){
/// y nam trong x
auto in = si.lower_bound((n - kids[u])/2);
if(in != si.end()){
calc(*in,n-kids[u]-(*in),kids[u]);
}
if(in != si.begin()){
auto pin = prev(in);
calc(*pin,n-kids[u]-(*pin),kids[u]);
}
/// y nam ngoai x
auto out = so.lower_bound((n - kids[u])/2);
if(out != so.end()){
calc(*out,n-kids[u]-(*out),kids[u]);
}
if(out != so.begin()){
auto pout = prev(out);
calc(*pout,n-kids[u]-(*pout),kids[u]);
}
si.insert(n - kids[u]);
for(auto v : g[u]) if(v != p){
solve(v,u);
}
so.insert(kids[u]);
si.erase(si.find(n - kids[u]));
}
int main(int argc,const char** argv){
cin >> n;
for(int i = 1;i < n;i++){
int x,y;
cin >> x >> y;
g[x].push_back(y);
g[y].push_back(x);
}
DFS(1);
solve(1);
cout << ans;
}
