#include <bits/stdc++.h>
using namespace std;
inline long long getnum() {
  char c = getchar();
  long long num;
  bool sign = false;
  for (; c < '0' || c > '9'; c = getchar())
    if (c == '-') sign = true;
  for (num = 0; c >= '0' && c <= '9';) {
    c -= '0';
    num = num * 10 + c;
    c = getchar();
  }
  return sign ? -num : num;
}
int gcd(int a, int b) { return (a && b) ? gcd(b, a % b) : (a + b); }
int A[500][500];
int B[500][500];
int XY[2006][2];
int C[2006][2];
int main() {
  long long n = getnum();
  long long ans = n * (n - 1) * (n - 2) / 6;
  for (int i = 1; i <= n; i++) XY[i][0] = getnum(), XY[i][1] = getnum();
  for (int i = 1; i <= n; i++) {
    int ind = 1;
    for (int j = i + 1; j <= n; j++) {
      int x = XY[j][0] - XY[i][0], y = XY[j][1] - XY[i][1];
      int g = gcd(abs(x), abs(y));
      x = x / g;
      y = y / g;
      if (x == 0)
        y = abs(y);
      else if (y == 0)
        x = abs(x);
      else if (x < 0 && y < 0)
        x = -x, y = -y;
      else if (x < 0 || y < 0)
        x = -1 * abs(x), y = abs(y);
      x += 200, y += 200;
      if (!A[x][y]) C[ind][0] = x, C[ind++][1] = y;
      A[x][y]++;
    }
    for (int i = 1; i < ind; i++) {
      int x = C[i][0], y = C[i][1];
      long long xx = A[x][y];
      ans -= xx * (xx - 1) / 2;
      A[x][y] = 0;
    }
  }
  cout << ans;
}
