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

count = 0
for i in range(n):
    for j in range(i+1, n):
        for k in range(j+1, n):
            x1, y1 = points[i]
            x2, y2 = points[j]
            x3, y3 = points[k]
            area = abs((x1-x3)*(y2-y3)-(x2-x3)*(y1-y3))
            if area != 0:
                count += 1

print(count)

   	     	   	 	 	  	 		  	 	