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.
# your code goes here
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):
            # calculate the area of the triangle formed by the i-th, j-th, and k-th points
            area = (points[j][0] - points[i][0]) * (points[k][1] - points[i][1]) \
                   - (points[k][0] - points[i][0]) * (points[j][1] - points[i][1])
            if area != 0:
                count += 1
 
print(count)
	   					 	 	 		  		 	 		 	 		