#include<cstdio>

#include<set>

#include<algorithm>

using namespace std;

int a[], b[];

set<double>ss;

int main()

{

    int n;

    scanf("%d", &n);

    for (int i = ; i < n; ++i)scanf("%d%d", &a[i], &b[i]);for (int i = ; i < n;++i)

    for (int j = i+; j < n; ++j)

    {

        if (a[i] == a[j]){ss.insert(); }

        else

        {

            double kk = (double)(b[i] - b[j]) / (double)(a[i] - a[j]);

            ss.insert(kk);

        }

    }

    printf("%d\n", ss.size());

}