#include <bits/stdc++.h>
using namespace std;
#define PB push_back
const int maxn = 2e5 + 5;
int n, ans = 0x3f3f3f3f;
int siz[maxn];
vector<int> tree[maxn];
inline void precalc(int u, int p){
siz[u] = 1;
for(int i = 0; i < tree[u].size(); ++i){
int v = tree[u][i];
if(v == p)
continue;
precalc(v, u);
siz[u] += siz[v];
}
return;
}
inline void calc(int x, int y, int z){
ans = min(ans, max(x, max(y, z)) - min(x, min(y, z)));
return;
}
inline void query(multiset<int> &S, int x, int k){
multiset<int>::iterator it = S.lower_bound(x);
if(it != S.end())
calc(*it, k, n - k - *it);
if(it != S.begin())
--it, calc(*it, k, n - k - *it);
return;
}
multiset<int> S, T;
inline void dfs(int u, int p){
query(S, (n - siz[u] + 1) / 2, siz[u]);
query(T, (n - siz[u] + 1) / 2, siz[u]);
S.insert(n - siz[u]);
for(int i = 0; i < tree[u].size(); ++i){
int v = tree[u][i];
if(v == p)
continue;
dfs(v, u);
}
S.erase(S.find(n - siz[u]));
T.insert(siz[u]);
return;
}
int main(){
//freopen("papricice.in", "r", stdin);
scanf("%d", &n);
for(int i = 1; i < n; ++i){
int u, v; scanf("%d%d", &u, &v);
--u, --v;
tree[u].PB(v), tree[v].PB(u);
}
precalc(0, -1);
dfs(0, -1);
printf("%d\n", ans);
return 0;
}
