#include <iostream>
#include <vector>

using namespace std;
int main()
{
    long int N;
    cin >> N;

    vector<vector<int>> XY(N);
    int seged;
    for (int i = 0; i < N; i++){
        cin >> seged;
        XY[i].push_back(seged);
        cin >> seged;
        XY[i].push_back(seged);

        XY[i].push_back(0);
    }

    /*for(int i = 0; i < N; i++){
        cout << XY[i][0] << XY[i][1];
    }*/

    int GotIt = 0;
    vector<vector<int>> Confirmed;
    for(int i = 0; i < N; i++){
        for(int j = 0; j < N; j++){
            //cout << XY[i][0] << ' ' << XY[j][0] << ' ' << XY[i][1] << ' ' << XY[i][0] << '\n';
            if((XY[i][0] == XY[j][0]) && (XY[i][1] != XY[j][1]))
                XY[i][2]++;
        }

        if(XY[i][2] != 0){
            for(int j = 0; j < N; j++){
            if((XY[i][1] == XY[j][1]) && (XY[i][0] != XY[j][0]))
                GotIt += XY[i][2];
            }
        }
    }

    cout << GotIt;
    return 0;
}