#include <bits/stdc++.h>

using namespace std;
ifstream fin("triang.in");
ofstream fout("triang.out");
int n;
float a[1502][3];
float distanta(float x1,float y1,float x2,float y2){
float dis=sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
return dis;
}
int main()
{
    cin>>n;
    for(int i=1;i<=n;++i)
        for(int j=1;j<=2;++j)
        cin>>a[i][j];
        int nr=0;
    for(int i=1;i<=n;++i)
    {
    for(int i1=i+1;i1<=n;++i1)
    {
    float dist1=distanta(a[i][1],a[i][2],a[i1][1],a[i1][2]);
    for(int i2=i+2;i2<=n;++i2){
   float dist2=distanta(a[i][1],a[i][2],a[i2][1],a[i2][2]);
   float dist3=distanta(a[i1][1],a[i1][2],a[i2][1],a[i2][2]);
    if(dist1==dist2&&dist1==dist3&&dist2==dist3)
        nr++;
    }
    }
    }
    cout<<nr;
    return 0;
}