#include <bits/stdc++.h>
using namespace std;
const int nx=2e5+5, kx=18;
int n, u, v, pa[nx][kx], sz[nx], in[nx], out[nx], rv[nx], t, res=1e9;
vector<int> d[nx];
multiset<int> ms;
void solve(int x, int y)
{
//cout<<x<<' '<<y<<' '<<n-x-y<<'\n';
res=min(res, max({x, y, n-x-y})-min({x, y, n-x-y}));
}
void dfs(int u, int p)
{
sz[u]=1;
in[u]=++t;
rv[t]=u;
pa[u][0]=p;
for (int i=1; i<kx; i++) pa[u][i]=pa[pa[u][i-1]][i-1];
for (auto v:d[u]) if (v!=p) dfs(v, u), sz[u]+=sz[v];
out[u]=t;
}
void sack(int u, int p, int del)
{
//cout<<"here "<<u<<'\n';
ms.erase(ms.find(sz[u]));
pair<int, int> hv;
for (auto v:d[u]) if (v!=p) hv=max(hv, {sz[v], v});
for (auto v:d[u]) if (v!=hv.second&&v!=p) sack(v, u, 1);
if (hv.second) sack(hv.second, u, 0);
for (auto v:d[u]) if (v!=hv.second&&v!=p) for (int i=in[v]; i<=out[v]; i++) ms.erase(ms.find(sz[rv[i]]));
/*
cout<<"finding "<<u<<'\n';
cout<<"ms ";
for (auto x:ms) cout<<x<<' ';
cout<<'\n';
*/
if (!ms.empty())
{
solve(sz[u], *prev(ms.upper_bound((n-sz[u])/2)));
if (ms.lower_bound((n-sz[u])/2)!=ms.end()) solve(sz[u], *ms.lower_bound((n-sz[u])/2));
}
v=u;
for (int i=kx-1; i>=0; i--) if (sz[pa[v][i]]-sz[u]<=n-sz[pa[v][i]]) v=pa[v][i];
solve(sz[u], n-sz[v]);
v=pa[v][0];
solve(sz[u], n-sz[v]);
if (del) for (int i=in[u]; i<=out[u]; i++) ms.insert(sz[rv[i]]);
}
int main()
{
//cin.tie(NULL)->sync_with_stdio(false);
cin>>n;
for (int i=1; i<n; i++) cin>>u>>v, d[u].push_back(v), d[v].push_back(u);
dfs(1, 1);
for (int i=1; i<=n; i++) ms.insert(sz[i]);
sack(1, 1, 0);
cout<<res;
}
