Vanya got bored and he painted *n* distinct points on the plane. After that he connected all the points pairwise and saw that as a result many triangles were formed with vertices in the painted points. He asks you to count the number of the formed triangles with the non-zero area.
The first line contains integer *n* (1 ≤ *n* ≤ 2000) — the number of the points painted on the plane. 

Next *n* lines contain two integers each *x*<sub class="lower-index">*i*</sub>, *y*<sub class="lower-index">*i*</sub> ( - 100 ≤ *x*<sub class="lower-index">*i*</sub>, *y*<sub class="lower-index">*i*</sub> ≤ 100) — the coordinates of the *i*-th point. It is guaranteed that no two given points coincide.
n,ans=int(input()),0
a=[]
for i in range(n):
  x,y=map(int,input().split())
  a.append([x,y])
for i in range(n):
  for j in range(i+1,n):
    for k in range(j+1,n):
      ans+=((a[j][0]-a[i][0])*(a[k][1]-a[i][1])!=(a[j][1]-a[i][1])*(a[k][0]-a[i][0]))
print(ans)