#include <bits/stdc++.h>
#define endl '\n'
#define int long long
using namespace std;

typedef pair<int, int> PII;

const int N = 100010;

int n;
vector<int> h[N];
int d[N];

void topsort()
{
    queue<int> q;
    for (int i = 1; i <= n; i++)
    {
        d[i] = h[i].size();
        if (d[i] == 1) q.push(i);
    }

    while (q.size())
    {
        auto t = q.front();
        q.pop();
        for (int i = 0; i < h[t].size(); i++)
        {
            int j = h[t][i];
            d[j]--;
            if (d[j] == 1) q.push(j);
        }
    }
}

signed main()
{
    ios ::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);

    cin >> n;
    for (int i = 1; i <= n; i++)
    {
        int u, v;
        cin >> u >> v;
        h[u].push_back(v), h[v].push_back(u);
    }

    topsort();

    int cnt = 0, m1 = 0, m2 = 0;
    for (int i = 1; i <= n; i++)
    {
        if (d[i] > 1)
        {
            cnt++;
            m1 = max(m1, (int)h[i].size());
        }
        else m2 = max(m2, (int)h[i].size());
    }
    
    if (m2 == 4) cout << cnt * (n - 1);
    else if (maxv < 4) cout << cnt * n << endl;
    else if (maxv == 4) cout << n * 2 + (cnt - 2) * (n - 1) << endl;
    else cout << (n - 1) * 2 << endl;

    return 0;
}

answer.code: In function ‘int main()’:
answer.code:63:14: error: ‘maxv’ was not declared in this scope
   63 |     else if (maxv < 4) cout << cnt * n << endl;
      |              ^~~~