#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pb push_back
#define irs insert
#define ed "\n"
#define fi first
#define se second
#define pi pair<int,int>
#define pii pair<int,pair<int,int>>
#define fis(i,a,b) for(int i=a;i<=b;++i)
#define fl(i,a,b) for(int i=a;i>=b;--i)
const int mod=1e9+7;
const int Mdem=998244353;
const int LOG=19;
const int base=31;
#define fast ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define gay(a) freopen(a".inp","r",stdin),freopen(a".out","w",stdout)
template <class T>
bool minimize(T &a, const T &b) {
if(a > b) {a = b; return 1;}
return 0;
}
template <class T>
bool maximize(T &a, const T &b) {
if(a < b) {a = b; return 1;}
return 0;
}
void add(int &a, int b) { a += b; if (a >= mod) a -= mod; }
void sub(int &a, int b) { a -= b; if (a < 0) a += mod; }
vector<int> adj[200005];
int sta[200005],fin[200005];
int n;
int par[200005];
int cnt=0;
int S[200005];
void dfs(int u)
{
sta[u]=++cnt;
for(int v:adj[u]){
if(v==par[u]) continue;
par[v]=u;
dfs(v);
}
fin[u]=cnt;
S[u]=fin[u]-sta[u]+1;
}
bool check(int u,int v) // ktra u co phai to ten v hay khong
{
return (sta[u]<=sta[v] && sta[v]<=fin[u]);
}
set<int> tt,ntt;
int ans=1e9;
void dfs1(int u){
if(u!=1) tt.irs(S[u]);
for(int v:adj[u]){
if(v==par[u]) continue;
par[v]=u;
auto lower=tt.lower_bound((n+S[v])/2);
if(lower!=tt.end()){
int x=*lower;
ans=min(ans, max({S[v],x-S[v],n-x }) - min({S[v],x-S[v],n-x }) );
}
if(lower!=tt.begin()){
--lower;
int xx=*lower;
ans=min(ans, max({S[v],xx-S[v],n-xx }) - min({S[v],xx-S[v],n-xx}) );
}
auto lower1=ntt.lower_bound((n-S[v])/2);
if(lower1!=ntt.end()){
int x1=*lower1;
ans=min(ans, max({S[v],x1,n-x1-S[v]}) - min({S[v],x1,n-x1-S[v]}) );
}
if(lower1!=ntt.begin()){
--lower1;
int x2=*lower1;
ans=min(ans, max({S[v],x2,n-x2-S[v]}) - min({S[v],x2,n-x2-S[v]}) );
}
dfs1(v);
}
tt.erase(S[u]);
ntt.irs(S[u]);
}
signed main(){
fast;
cin>>n;
fis(i,1,n-1)
{
int x,y;
cin>>x>>y;
adj[x].pb(y);
adj[y].pb(x);
}
for(int i=1;i<=n;++i) sort(adj[i].begin(),adj[i].end());
dfs(1);
memset(par,0,sizeof par);
dfs1(1);
cout<<ans;
return 0;
}
