#include <bits/stdc++.h>
using namespace std;
template <class T>
inline T bigmod(T p, T e, T M) {
  long long ret = 1;
  for (; e > 0; e >>= 1) {
    if (e & 1) ret = (ret * p) % M;
    p = (p * p) % M;
  }
  return (T)ret;
}
template <class T>
inline T gcd(T a, T b) {
  if (b == 0) return a;
  return gcd(b, a % b);
}
template <class T>
inline T modinverse(T a, T M) {
  return bigmod(a, M - 2, M);
}
pair<int, int> pp[2001], ar[2001];
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  long long n;
  cin >> n;
  for (int i = (0); i < (n); ++i) cin >> pp[i].first >> pp[i].second;
  long long res = (n * (n - 1) * (n - 2)) / 6ll, sum = 0;
  for (int i = (0); i < (n); ++i) {
    int cnt = 0;
    for (int j = (0); j < (n); ++j)
      if (i != j) {
        ar[cnt].first = pp[j].first - pp[i].first;
        ar[cnt].second = pp[j].second - pp[i].second;
        cnt++;
      }
    for (int j = (0); j < (cnt); ++j) {
      int v = gcd(ar[j].first, ar[j].second);
      v = abs(v);
      if (v == 0) continue;
      ar[j].first /= v;
      ar[j].second /= v;
    }
    sort(ar, ar + cnt);
    int last = -1;
    for (int j = 0; j < cnt; j++) {
      if (j == cnt - 1 || ar[j] != ar[j + 1]) {
        int tot = j - last;
        sum += (tot * (tot - 1)) / 2;
        last = j;
      }
    }
  }
  cout << res - (sum / 2) << endl;
}
