#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int N=200005;
int n,m,k,s,t,sz[N],ans=0x3f3f3f3f;
multiset<int> s1,s2;
multiset<int>::iterator it;
vector<int> e[N];
void check(int a,int b){
	int c=n-a-b;
	int p=max(max(a,b),c);
	int q=min(min(a,b),c);
	ans=min(ans,p-q);
}
void dfs(int u,int fa){
	sz[u]=1;
	for (int &v:e[u]){
		if (v==fa) continue;
		dfs(v,u);
		sz[u]+=sz[v];
	}
}
void dfs1(int u,int fa){
	it=s1.lower_bound((n-sz[u])/2);
	if (it!=s1.end()) check(sz[u],*it);
	if (it!=s1.begin()) {
		--it;
		check(sz[u],*it);
	}
	it=s2.lower_bound((n+sz[u])/2);
	if (it!=s2.end()) check(sz[u],*it-sz[u]);
	if (it!=s2.end()) {
		--it;
		check(sz[u],*it-sz[u]);
	}
	s2.insert(sz[u]);
	for (int &v:e[u]){
		if (v==fa) continue;
		dfs1(v,u);
 	}
	s2.erase(s2.find(sz[u]));
	s1.insert(sz[u]);
}
int main(){
	freopen("in.txt","r",stdin);
	cin>>n;
	for (int i=1;i<n;++i){
		cin>>s>>t;
		e[s].push_back(t);
		e[t].push_back(s);
	}
	dfs(1,0);
	dfs1(1,0);
	cout<<ans;
}