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.
'''
4
0 0
1 1
2 0
2 2
'''
from itertools import combinations

if __name__ == '__main__':
    n=int(input())
    pos=[]
    for i in range(n):
        x,y=map(int,str(input()).split(" "))
        p=[x,y]
        pos.append(p)
    max = 0;

    for i in range(n):
        for j in range(i+1,n):
            for k in range(j+1,n):
                area=int(pos[i][0]*(pos[j][1]-pos[k][1]) + pos[j][0]*(pos[k][1]-pos[i][1]) + pos[k][0]*(pos[i][1]-pos[j][1]))
                if(area != 0):
                  max=max+1



    print(max)
