#include <bits/stdc++.h>
using namespace std;
const int MAXN = 2E3 + 10, MAXM = 200 + 10;
int n;
int x[MAXN], y[MAXN];
int gcd(int a, int b) { return b ? gcd(b, a % b) : a; }
pair<int, int> get_pair(int a, int b) {
  if (a == 0) return make_pair(0, 1);
  int d = gcd(a, b);
  a /= d;
  b /= d;
  if (a < 0) {
    a *= -1;
    b *= -1;
  }
  return make_pair(a, b);
}
int main() {
  scanf("%d", &n);
  for (int i = 0; i < n; ++i) scanf("%d%d", &x[i], &y[i]);
  long long sum = 0;
  for (int i = 0; i < n; ++i) {
    vector<pair<int, int> > lst;
    lst.reserve(n - 1);
    for (int j = 0; j < n; ++j)
      if (i != j) lst.push_back(get_pair(x[i] - x[j], y[i] - y[j]));
    sort(lst.begin(), lst.end());
    for (int k, j = 0; j < n - 1; j = k) {
      for (k = j + 1; k < n - 1 && lst[j] == lst[k]; ++k)
        ;
      sum += (k - j) * (n - 1 - k + j);
    }
  }
  sum /= 6;
  printf("%I64d", sum);
  return 0;
}
