#include <bits/stdc++.h> #define pb push_back #define fi first #define se second typedef long long ll; using namespace std; ll n, ans; pair<ll,ll>arr[300005]; int main(){ cin >> n; for(int i = 0; i < n; i++){ cin >> arr[i].fi >> arr[i].se; } for(int i = 0; i < n; i++){ for(int j = 0; j < n; j++){ if(i==j)continue; for(int k = 0; k < n; k++){ if(j==k || i == k) continue; if(arr[i].fi == arr[j].fi && arr[j].se == arr[k].se){ ans++; } } } } cout << ans << endl; } //tle lmao