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 = int(input())
points = [ [ int(i) for i in input().split() ] for _ in range(n) ]

area = lambda a, b, c: abs( ((a[0] - c[0]) * (b[1] - a[1])) - ((a[0] - b[0]) * (c[1] - a[1])) )

c = 0
for i in range(n):
    for j in range(i, n):
        for k in range(j, n):
            if area(points[i], points[j], points[k]) != 0:
                c += 1

print(c)