#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define int long long
#define FOR(i, a, b) for ( int i = a ; i <= b ; i++ )
#define FORD(i, a, b) for (int i = b; i >= a; i --)
#define REP(i, n) for (int i = 0; i < n; ++i)
#define REPD(i, n) for (int i = n - 1; i >= 0; --i)
#define pii pair<int , int>
#define Lg(x) 31 - __builtin_clz(x)
#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)
constexpr ll LINF = (1ll << 60);
constexpr int INF = (1ll << 30);
constexpr int MAX = 2e5 + 5;
constexpr int Mod = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
void setupIO(){
#define name "Whisper"
//Phu Trong from Nguyen Tat Thanh High School for gifted student
srand(time(NULL));
cin.tie(nullptr)->sync_with_stdio(false); cout.tie(nullptr);
//freopen(name".inp", "r", stdin);
//freopen(name".out", "w", stdout);
cout << fixed << setprecision(10);
}
template <class X, class Y>
bool minimize(X &x, const Y &y){
X eps = 1e-9;
if (x > y + eps) {x = y; return 1;}
return 0;
}
template <class X, class Y>
bool maximize(X &x, const Y &y){
X eps = 1e-9;
if (x + eps < y) {x = y; return 1;}
return 0;
}
int numNode;
vector<int> adj[MAX];
int sz[MAX];
void reSubsize(int u, int p = -1){
sz[u] = 1;
for (auto&v : adj[u]) if(v ^ p){
reSubsize(v, u);
sz[u] += sz[v];
}
}
int optimize(int a, int b, int c){
return max({a, b, c}) - min({a, b, c});
}
int ans = INF;
set<int> a, b;
vector<int> compute(set<int>&x, int v){
auto it = x.lower_bound(v);
vector<int> res;
if (it != x.end()) res.push_back(*it);
if (it != x.begin()) res.push_back(*(--it));
return res;
}
void dfs(int u, int p){
for (int szA : compute(a, (numNode + sz[u]) / 2)){
minimize(ans, optimize(sz[u], szA - sz[u], numNode - szA));
}
for (int szB : compute(b, (numNode - sz[u]) / 2)){
minimize(ans, optimize(sz[u], szB, numNode - sz[u] - szB));
}
a.insert(sz[u]);
for (auto&v : adj[u]) if(v ^ p){
dfs(v, u);
}
a.erase(sz[u]);
b.insert(sz[u]);
}
void Whisper(){
cin >> numNode;
for (int i = 1; i < numNode; ++i){
int u, v; cin >> u >> v;
adj[u].push_back(v);
adj[v].push_back(u);
}
reSubsize(1);
dfs(1, 0);
cout << ans;
}
signed main(){
setupIO();
int Test = 1;
// cin >> Test;
for ( int i = 1 ; i <= Test ; i++ ){
Whisper();
if (i < Test) cout << '\n';
}
}
