#include <bits/stdc++.h>
using namespace std;
#define int long long
#define N (int)2e5 + 5
#define pdd pair<double, double>
#define pii pair<int, int>

int a, b, c, d, x, y, n, m, t, k, q, l, r, p, z, h;
int num[N], in[N];
int cnt[N];
stack<int> st;
string s;
map<int, int> mp;
int f = 0;
vector<int> g[N];
pii edge[N];
void dfs(int now, int fa) {
    if (f) return;
    if (in[now]) {
        do {
            y = st.top();
            st.pop();
            mp[y] = 1;
        } while (y != now);
        f = 1;
        return;
    }
    in[now] = 1;
    st.push(now);
    for (auto &i : g[now]) {
        if (i != fa)
            dfs(i, now);
    }
    in[now] = 0;
}
signed main() {
	ios::sync_with_stdio(false), cin.tie(0), cout.tie(0);
	// 注意根据数据量调整N的大小
    cin >> n;
//    cout << edge[0].first << ' ' << edge[1].second << '\n';
    for (int i = 1; i <= n; i++) {
        cin >> x >> y;
        g[x].push_back(y);
        g[y].push_back(x);
        edge[i] = {x, y};
        cnt[x]++;
        cnt[y]++;
    }
    dfs(1, 0);
//    for (auto it = mp.begin(); it != mp.end(); it++) {
//        cout << it->first << '\n';
//    }
    int c5, c3;
    c5 = c3 = 0;
    for (int i = 1; i <= n; i++) {
        if (cnt[i] >= 5) c5++;
        else if (cnt[i] <= 3) c3++;
    }
//    cout << c3 << ' ' << c5 << '\n';
    int ans = 0;
    for (int j = 1; j <= n; j++) {
        pii i = edge[j];
        int c55 = c5, c33 = c3;
        if (!mp.count(i.first) || !mp.count(i.second)) continue;
        if (cnt[i.first]>=5&&cnt[i.first]-1<5) c55--;
        else if (cnt[i.first]>3&&cnt[i.first]-1<=3) c33++;

        if (cnt[i.second]>=5&&cnt[i.second]-1<5) c55--;
        else if (cnt[i.second]>3&&cnt[i.second]-1<=3) c33++;

//        cout << i.first << ' ' << i.second << ' ' << c3 << ' ' << c5 << '\n';

        if (!c55) ans += c33;
    }
    if (n == 2) {
        cout << 4 << '\n';
    } else cout << ans << '\n';
	return 0;
}