#include<bits/stdc++.h>
using namespace std;
#define int long long
#define lowbit(x) (x & (-x))
typedef long long ll;
typedef pair<int,int> pii;
mt19937 rnd(time(0));
const int N = 1e7 + 7;
const int mod = 1e9 + 9;
int pre[N] , n;
vector<int> e[N];
bool vis[N]; 
void find() {
    for(int i = 1;i <= n;i++) {
        if(e[i].size() == 1) {
            queue<int> q,qt; 
            q.push(i);
            pre[i] = 0;
            bool f = 0;
            while(!q.empty()) {
                if(f) break;
                int u = q.front();
                q.pop();
                for(auto v : e[u]) {
                    if(v != pre[u]) {
                        if(!pre[v]) {
                            pre[v] = u;
                            q.push(v);
                        }
                        else {
                            qt.push(v); //让较长的点先入队，方便后续返回，较长的点一定是被找到的
                            qt.push(u);
                            f = 1;
                            break;
                        }
                    }
                }
            }
            while(!qt.empty()) {
                int u = qt.front();
                qt.pop();
                if(vis[u]) break;
                vis[u] = 1;
                qt.push(pre[u]);
            }
            return ;
        }
    }
    for(int i = 1;i <= n;i++) vis[i] = 1;
    return ;
}
void solve() {
    cin >> n;
    for(int i = 1;i <= n;i++) {
        int u , v; cin >> u >> v;
        e[u].push_back(v);
        e[v].push_back(u);
    }
    find();
    vector<int> vv;
    for(int i = 1;i <= n;i++) {
        if(vis[i]) vv.push_back(i);
    }
    int res = 0,ans = 0;
    for(int i = 1;i <= n;i++) {
        if(e[i].size() <= 3) res++;
    }
    for(int i = 0;i < vv.size();i++) {
        if(e[i].size() == 5) {
            for(auto x : e[i]) {
                if(vis[x]) {
                    if(e[x].size() == 5) {
                        cout << res << "\n";
                        return ;
                    }
                    else ans += res + (e[x].size() == 4);
                }
            }
            cout << ans << "\n";
            return ;
        }
    }
    for(int i = 0;i < vv.size();i++) {
        if(e[i].size() == 4) {
            for(auto x : e[i]) {
                if(vis[x]) {
                    if(e[i].size() == 4) ans += res + 2;
                    else ans += res + 1;
                }
            }
        }
        else {
            for(auto x : e[i]) {
                if(vis[x]) {
                    if(e[i].size() == 4) ans += res + 1;
                    else ans += res;
                }
            }
        }
    }
    cout << ans / 2 << "\n";
}
signed main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int t = 1;
    // cin >> t;
    while(t--) solve();
    return 0;
}