#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
#define F first
#define S second
#define ALL(x) x.begin(), x.end()
#define MEM(x) memset(x, 0, sizeof(x))
#define MEMS(x) memset(x, -1, sizeof(x))
#define eb emplace_back
#define ep emplace
#define mkp make_pair
const int INF = 0x3f3f3f3f;
const ll LINF = 0x3f3f3f3f3f3f3f3f;
/*------------------------------------------------------------------*/
const int N = 2000 + 5;
vector<int> G[N];
vector<pii> edge;
int sz[N];
void dfs(int u, int p) {
sz[u] = 1;
for(auto& v : G[u]) if(v != p) {
dfs(v, u);
sz[u] += sz[v];
}
}
inline void solve() {
int n; cin >> n;
for(int i = 0; i < n - 1; ++i) {
int u, v; cin >> u >> v;
G[u].eb(v);
G[v].eb(u);
edge.eb(u, v);
}
int ans = N;
for(auto& x : edge) {
MEM(sz);
dfs(x.F, x.S);
for(int i = 0; i < n; ++i) {
int mx = max({n - sz[x.F], sz[x.F] - sz[i], sz[i]});
int mn = min({n - sz[x.F], sz[x.F] - sz[i], sz[i]});
ans = min(ans, mx - mn);
}
MEM(sz);
dfs(x.S, x.F);
for(int i = 0; i < n; ++i) {
int mx = max({n - sz[x.S], sz[x.S] - sz[i], sz[i]});
int mn = min({n - sz[x.S], sz[x.S] - sz[i], sz[i]});
ans = min(ans, mx - mn);
}
}
cout << ans << '\n';
}
int main() {
cin.tie(0), ios::sync_with_stdio(0);
solve();
}
