#include <bits/stdc++.h>
using namespace std;
template <typename T1, typename T2>
inline void mine(T1 &x, const T2 &y) {
  if (y < x) x = y;
}
template <typename T1, typename T2>
inline void maxe(T1 &x, const T2 &y) {
  if (x < y) x = y;
}
template <typename T>
ostream &operator<<(ostream &os, const vector<T> &b) {
  for (auto &k : b) os << k << ' ';
  return os;
}
template <typename T>
istream &operator>>(istream &is, vector<T> &b) {
  for (auto &k : b) is >> k;
  return is;
}
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
long long gcd(long long x, long long y) {
  x = abs(x);
  y = abs(y);
  while (y) {
    x %= y;
    swap(x, y);
  }
  return x;
}
const long long N = 2010;
long long x[N];
long long y[N];
int32_t main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  long long n;
  cin >> n;
  long long ans = n * (n - 1) * (n - 2) / 6;
  for (long long i = 0; i < n; ++i) {
    cin >> x[i] >> y[i];
    vector<pair<long long, long long> > kek;
    for (long long j = 0; j < i; ++j) {
      long long dx = x[i] - x[j];
      long long dy = y[i] - y[j];
      if (dx < 0) {
        dx *= -1;
        dy *= -1;
      }
      if (dx == 0) dy = abs(dy);
      long long g = gcd(dx, dy);
      dx /= g;
      dy /= g;
      kek.push_back({dx, dy});
    }
    sort(kek.begin(), kek.end());
    long long len = 0;
    for (long long k = 0; k < (long long)kek.size(); ++k) {
      if (k == 0 || kek[k] != kek[k - 1]) len = 0;
      ++len;
      ans -= len - 1;
    }
  }
  cout << ans << '\n';
}
