#include <bits/stdc++.h>
using namespace std;
using pii = pair<int,int>;
const int INF = 1e9;
int n;
vector<vector<int>> adj, children;
vector<int> tin, tout, euler, sz;
int timer;
vector<int> B;
vector<vector<int>> bests;
int ans;
void dfs1(int u, int p){
sz[u] = 1;
tin[u] = ++timer;
euler[timer] = u;
for(int v: adj[u]){
if(v==p) continue;
children[u].push_back(v);
dfs1(v,u);
sz[u] += sz[v];
}
tout[u] = timer;
}
void forward_scan(){
multiset<int> st;
vector<vector<int>> nodesAtTin(n+1);
for(int u=2; u<=n; u++){
nodesAtTin[tin[u]].push_back(u);
}
for(int i=1; i<=n; i++){
for(int u: nodesAtTin[i]){
int r = n - sz[u];
int target = r/2;
if(!st.empty()){
auto it = st.lower_bound(target);
if(it!=st.end()) bests[u].push_back(*it);
if(it!=st.begin()){
--it;
bests[u].push_back(*it);
}
}
}
st.insert(B[i]);
}
}
void backward_scan(){
multiset<int> st;
vector<vector<int>> nodesAtTout(n+2);
for(int u=2; u<=n; u++){
nodesAtTout[tout[u]].push_back(u);
}
for(int i=n; i>=1; i--){
for(int u: nodesAtTout[i]){
int r = n - sz[u];
int target = r/2;
if(!st.empty()){
auto it = st.lower_bound(target);
if(it!=st.end()) bests[u].push_back(*it);
if(it!=st.begin()){
--it;
bests[u].push_back(*it);
}
}
}
st.insert(B[i]);
}
}
set<int>* dfs_dsu(int u){
auto *S = new set<int>();
S->insert(sz[u]);
for(int v: children[u]){
auto *Sv = dfs_dsu(v);
if(S->size() < Sv->size()) swap(S, Sv);
for(int x: *Sv) S->insert(x);
delete Sv;
}
int s = sz[u];
int r = n - s;
int target = s/2;
if(!S->empty()){
auto it = S->lower_bound(target);
vector<int> cands;
if(it!=S->end()) cands.push_back(*it);
if(it!=S->begin()){
--it;
cands.push_back(*it);
}
for(int a: cands){
int b = s - a;
int mx = max({a,b,r});
int mn = min({a,b,r});
ans = min(ans, mx - mn);
}
}
for(int a: bests[u]){
int b = (n - s) - a;
int c = s;
int mx = max({a,b,c});
int mn = min({a,b,c});
ans = min(ans, mx - mn);
}
return S;
}
int main(){
ios::sync_with_stdio(false);
cin.tie(nullptr);
cin >> n;
adj.assign(n+1,{});
children.assign(n+1,{});
tin.assign(n+1,0);
tout.assign(n+1,0);
euler.assign(n+1,0);
sz.assign(n+1,0);
B.assign(n+1,0);
bests.assign(n+1,{});
timer = 0;
for(int i=1,x,y;i<n;i++){
cin >> x >> y;
adj[x].push_back(y);
adj[y].push_back(x);
}
dfs1(1,0);
for(int i=1;i<=n;i++){
B[i] = sz[euler[i]];
}
forward_scan();
backward_scan();
ans = n;
auto *unused = dfs_dsu(1);
delete unused;
cout << ans << "\n";
return 0;
}
