#include <bits/stdc++.h>
#pragma comment(linker, "/STACK:256000000")
using namespace std;
long long gcd(long long a, long long b) {
  while (b) b ^= a ^= b ^= a %= b;
  return a;
}
int main() {
  srand(1373737);
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  int n;
  cin >> n;
  vector<pair<long long, long long> > arr(n);
  for (int i = 0; i < n; i++) {
    cin >> arr[i].first >> arr[i].second;
  }
  pair<long long, long long> cur, curo;
  long long c, d;
  set<pair<pair<long long, long long>, long long> > ss;
  long long ans = 0ll;
  for (int i = 0; i < n; i++) {
    for (int j = i + 1; j < n; j++) {
      cur =
          make_pair(arr[i].first - arr[j].first, arr[i].second - arr[j].second);
      curo = make_pair(-cur.second, cur.first);
      d = gcd(abs(curo.first), abs(curo.second));
      curo.first /= d;
      curo.second /= d;
      if (curo.first < 0ll) {
        curo.first = -curo.first;
        curo.second = -curo.second;
      } else if (curo.first == 0ll && curo.second < 0ll) {
        curo.first = -curo.first;
        curo.second = -curo.second;
      }
      c = -(curo.first * arr[i].first + curo.second * arr[i].second);
      ss.insert(make_pair(curo, c));
    }
  }
  vector<pair<pair<long long, long long>, long long> > lines =
      vector<pair<pair<long long, long long>, long long> >(ss.begin(),
                                                           ss.end());
  map<pair<long long, long long>, long long> have;
  n = (int)lines.size();
  for (int i = 0; i < n; i++) {
    long long k = (long long)(n - i - 1) - have[lines[i].first];
    ans += k;
    have[lines[i].first]++;
  }
  cout << ans;
  return 0;
}
