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#include <bits/stdc++.h>
#define ull unsigned long long
#define FILES freopen("darb.in","r",stdin);\
freopen("darb.out","w",stdout);
#define CMAX 1000000
#define fastio std::ios_base::sync_with_stdio(NULL),cin.tie(NULL),cout.tie(NULL);
#define mp make_pair
#define INF 999999999999999
#define mod 1000000007
#define ll long long
#define MAX 100000
#define SMAX 500000
#define pb push_back
#define add emplace_back
using namespace std;
int n,fr[MAX+5],ans,z;
bool ok[MAX+5];
pair<int,int> dp[MAX+5];
vector<int> v[MAX+5];
void GetFr(int x)
{
ok[x] = 1;
for(auto i : v[x])
{
if(!ok[i])
{
GetFr(i);
fr[x]++;
}
}
}
void dfs(int x,int y,int dist)
{
fr[x] = 1;
if(x == z)
{
ans += dist;
return;
}
for(auto i : v[x])
{
if(!fr[i])
dfs(i,y,dist+1);
}
}
int main()
{
FILES
cin >> n;
for(int i = 1;i < n; ++i)
{
int a,b;
cin >> a >> b;
v[a].add(b),v[b].add(a);
}
GetFr(1);
queue<int> q;
for(int i = 1;i <= n; ++i)
if(!fr[i]) q.push(i),dp[i].first = i;
while(!q.empty())
{
int x = q.front();
if(dp[x].first || dp[x].second) z = x;
for(auto i : v[x])
{
fr[i]--;
if(fr[i] >= 0) dp[i].second = dp[i].first,dp[i].first = dp[x].first;
if(!fr[i]) q.push(i);
}
q.pop();
}
memset(fr,false,sizeof(fr));
dfs(dp[z].first,z,0);
memset(fr,false,sizeof(fr));
if(dp[z].second)
dfs(dp[z].second,z,0);
cout << ans + 1;
}