#include<bits/stdc++.h>
using namespace std;

const int N = 1e5+10;


vector<int> v[N];
#define pii array<int,2>
vector<pii> ed;

int vis[N];
int siz[N],mx[N];//分别是全部子树数量和最大儿子数量
stack<int> st;
int flag = 0;
int ans =0 ;
void dfs1(int x,int f){
    for(int y : v[x]){
        if(flag)return;

        if(y==f)continue;
        if(vis[y]){//已经是环了
            int x = st.top();
            st.pop();
            
            int last = x;
            while(!st.empty()&&st.top()!=x){
                int now = st.top();
                ed.push_back({last,now});
                st.pop();
                last = now;
            }
            ed.push_back({last,x});
            flag = 1;
            return;
        }
        vis[y] = 1;
        st.push(y);
        dfs1(y,x);
        st.pop();
    }
}
int du[N];

void solve(){
    int n;
    cin>>n;
    for(int i = 1;i<=n;i++){
        int a,b;
        cin>>a>>b;
        du[a]++;
        du[b]++;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    map<int,int> mp;
    st.push(1);
    vis[1] = 1;
    dfs1(1,0);
    int mx = 0;
    for(int i = 1;i<=n;i++){
        mx = max(mx,du[i]);
        mp[du[i]]++;
    }
    if(mx>5){
        cout<<0<<'\n';
        return;
    }
    int ans = 0;
    for(auto h : ed){
        int x = h[0],y = h[1];
        int dx = du[x],dy = du[y];
        mp[dx]--,mp[dy]--;
        mp[dx-1]++,mp[dy-1]++;
        if(mp[5]==0){
            ans+=mp[3];
            ans+=mp[2];
            ans+=mp[1];
        }
        mp[dx]++,mp[dy]++;
        mp[dx-1]--,mp[dy-1]--;
    }
    cout<<ans<<'\n';
}
/*
6
1 2
1 3
1 4
1 5
1 6
2 3
*/
signed main(){
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    int t = 1;
    // cin>>t;
    while(t--)
    solve();
    return 0;
}