#include <bits/stdc++.h>
using namespace std;
const int N = 3005;
long double x[N], y[N];
int main() {
  int n;
  scanf("%d", &n);
  for (int i = 1; i <= n; i++) {
    cin >> x[i] >> y[i];
  }
  long long res = 1ll * n * (n - 1) * (n - 2) * (n - 3) * (n - 4) / 24;
  long double pi = acos(-1.0L);
  for (int i = 1; i <= n; i++) {
    vector<long double> v;
    for (int j = 1; j <= n; j++) {
      if (i == j) continue;
      v.push_back(atan2(y[j] - y[i], x[j] - x[i]));
    }
    sort(v.begin(), v.end());
    int m = n - 1, index = 0;
    for (int j = 0; j < m; j++) {
      while (index < j + m) {
        long double ang = v[index % m] - v[j];
        if (ang < 0) ang += 2 * pi;
        if (ang < pi)
          index++;
        else
          break;
      }
      long long cnt = index - j - 1;
      res -= 1ll * cnt * (cnt - 1) * (cnt - 2) / 6;
    }
  }
  cout << res << endl;
  return 0;
}
