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.
def area_triangle(a , b, c):
	return a[0]*b[1] - a[1]*b[0] + b[0]*c[1] - b[1]*c[0] + c[0]*a[1] - c[1]*a[0];

n = int(input())
points = []
for j in range(n):
	l = [int(x) for x in input().split()]
	points.append(l)

count = 0
for x in range(n):
	for y in range(x+1, n):
		for j in range(y+1, n):
			if(area_triangle(points[x], points[y], points[j])):
				count +=1
print(count)
