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())

x = [0]*n
y = [0]*n
for i in range(n):
	x[i], y[i] = map(int, input().split())

res = 0
for i in range(n):
	for j in range(i+1, n):
		p1 = x[j] - x[i]
		p2 = y[j] - y[i]
		p3 = x[j]*y[i] - y[j]*x[i]
		for k in range(j+1, n):
			if (p1*y[k] - p2*x[k]) != p3:
				res += 1
print(res)