#include <bits/stdc++.h> using namespace std; const int MAXN = 2e5 + 10, INF = 1e9; vector<int> e[MAXN]; int sz[MAXN], lo[MAXN], hi[MAXN], tick; int dfs(int x, int p) { lo[x] = tick++; sz[x] = 1; for (auto y : e[x]) { if (y != p) sz[x] += dfs(y, x); } hi[x] = tick; return sz[x]; } int balance(int a, int b, int c) { return max({a, b, c}) - min({a, b, c}); } int main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); int n; cin >> n; for (int i = 0; i < n - 1; i++) { int x, y; cin >> x >> y; e[x].push_back(y); e[y].push_back(x); } dfs(1, -1); int sol = INF; for (int x = 2; x <= n; x++) { for (int y = x + 1; y <= n; y++) { if (lo[x] < lo[y] && lo[y] < hi[x]) sol = min(sol, balance(sz[y], sz[x] - sz[y], n - sz[x])); else if (lo[y] < lo[x] && lo[x] < hi[y]) sol = min(sol, balance(sz[x], sz[y] - sz[x], n - sz[y])); else sol = min(sol, balance(sz[x], sz[y], n - sz[x] - sz[y])); } } cout << sol << '\n'; return 0; }