#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define fi first
#define se second
#define all(x) x.begin(),x.end()
const ll MAXN=3e5+5,MOD=1e9+7,INF=1e18;
ll i,n,m,j,k,p,ans,cnt,dem,de[MAXN],id[MAXN],sz[MAXN],par[MAXN],en[MAXN],nen[MAXN],parma[MAXN];
vector<ll> adj[MAXN];
void dfs(ll u,ll pre,ll parup){
sz[u]=1;
id[u]=++cnt;
nen[cnt]=u;
parma[u]=parup;
for(auto x:adj[u]){
if(x==pre) continue;
if(u==1) parup=x;
par[x]=u;
de[x]=de[u]+1;
dfs(x,u,parup);
sz[u]+=sz[x];
}
en[u]=cnt;
}
multiset<ll> se1,se2;
void calc(ll a,ll b,ll c){
ans=min(ans,max({a,b,c})-min({a,b,c}));
}
void tinh(ll u){
auto it=se1.lower_bound(sz[u]/2);
if(it!=se1.end()){
ll val=*it;
calc(n-val,val-sz[u],sz[u]);
}
if(it!=se1.begin()){
it--;
ll val=*it;
calc(n-val,val-sz[u],sz[u]);
}
}
void tinh1(ll u){
auto it=se2.lower_bound((n-sz[u])/2);
if(it!=se2.end()){
ll val=*it;
calc(n-val-sz[u],sz[u],val);
}
if(it!=se2.begin()){
it--;
ll val=*it;
calc(n-val-sz[u],sz[u],val);
}
}
void solve(ll u,ll pre){
tinh(u);
tinh1(u);
se1.insert(sz[u]);
for(ll x:adj[u]){
if(x==pre) continue;
solve(x,u);
}
se1.erase(se1.find(sz[u]));
se2.insert(sz[u]);
}
int main(){
ios::sync_with_stdio(0);
cin.tie(0);cout.tie(0);
// freopen("test.inp","r",stdin);
// freopen("test.out","w",stdout);
cin>>n;
for(i=1;i<n;i++){
ll u,v;
cin>>u>>v;
adj[u].pb(v);
adj[v].pb(u);
}
dfs(1,1,1);
ans=INF;
solve(1,1);
cout<<ans;
}
