#include <fstream>
#include <algorithm>
#include <cmath>
using namespace std;

int n,nrt;
struct P{double x,y;}a[1503];

double dist(P x,P y)
{
	return (x.x-y.x)*(x.x-y.x)+(x.y-y.y)*(x.y-y.y);
}

bool equal(double x,double y)
{
	if (fabs(x-y)>1e-3)return 0;
	return 1;
}

bool compare(P t, P yt)
{
	return t.x>yt.x;
}

int main()
{
	int i,j,k;
	ifstream in("triang.in");
	in>>n;
	for(i=0;i<n;i++)
		in>>a[i].x>>a[i].y;
	in.close();
	sort(a,a+n,compare);
	for(i=0;i<n;i++)
		for(j=i+1;j<n;j++)
			for(k=j+1;k<n;k++)
				if(equal(dist(a[i],a[j]),dist(a[j],a[k]))&&equal(dist(a[j],a[k]),dist(a[k],a[i])) )
				{
					nrt++;
					break;
				}
	ofstream("triang.out")<<nrt<<'\n';
	return 0;
}