#include <cstring>
#include <stdio.h>
#include <algorithm>
#include <iostream>
#include <cmath>
#include <map>
#include <string>
#include <queue>
#include <bitset>
using namespace std;

typedef long long ll;

int n;
struct Point
{
    int x,y;
}p[25];

int dis2(Point a,Point b)
{
    return (a.x -b.x)*(a.x - b.x) + (a.y - b.y)*(a.y-b.y);
}
int chaji(Point a,Point b,Point c)
{
    return (a.x-b.x)*(c.x-b.x) + (a.y-b.y)*(c.y-b.y);
}

bool ok(Point a,Point b,Point c)
{
    if(chaji(a,b,c) == 0 && dis2(a,b) == dis2(b,c))
        return true;
    return false;
}
int main()
{
//    freopen("in.txt","r",stdin);
    while(scanf("%d",&n) != EOF)
    {
        int a,b;
        for(int i=0;i<n;i++)
        {
            scanf("%d%d",&p[i].x,&p[i].y);
        }
        ll ans = 0;
        for(int i=0;i<n;i++)
        {
            
            for(int j=0;j<n;j++)
            {
                if(j == i) continue;
                for(int k=0;k<n;k++)
                {
                    if(k == i || k == j) continue;
                    for(int q=0;q<n;q++)
                    {
                        if(q == i ||q == j || q == k) continue;
                        Point a = p[i];
                        Point b = p[j];
                        Point c = p[k];
                        Point d = p[q];
                        if(ok(a,b,c) && ok(b,c,d) && ok(c,d,a) && ok(d,a,b))
                        {
                            ans ++;
                        }
                    }
                }
            }
        }

        printf("%I64d\n",ans/8 );
    }
    //while(1);

}