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())

if n < 3:
	print(0)
else:
    ans = n*(n-1)*(n-2)/6
    x = [0]*n
    y = [0]*n
    for i in range(n):
    	x[i], y[i] = map(int, input().split())
    for i in range(n):
        seen = {}
        x1, y1 = x[i], y[i]
        for j in range(i+1, n):
            x2, y2 = x[j], y[j]
            if x2-x1 == 0:
            	m = 1e999
            else:
                m = (y2-y1)*1.0/(x2-x1)
            if m not in seen:seen[m] = 0
            ans -= seen[m]
            seen[m] += 1
    print(int(ans))