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.
import itertools

n=int(input())
c=[]
for x in range(n):
	c.append([int(x) for x in input().split()])
co=0
for z in list(itertools.combinations(c,3)):
	z0x,z0y=z[0]
	z1x,z1y=z[1]
	z2x,z2y=z[2]
	if(z0x*z1y-z0y*z1x+z1x*z2y-z1y*z2x+z2x*z0y-z2y*z0x!=0):
		co+=1
print(co)