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())
cordx = []
cordy= []
for z in range(n):
	x, y = map(int,input().split(" "))
	cordx.append(x)
	cordy.append(y)
count=0
for i in range(0,n):
	Ax=cordx[i]
	Ay=cordy[i]
	for j in range(i+1,n):
		Bx = cordx[j]
		By = cordy[j]
		ABx= Bx-Ax
		ABy= By-Ay
		for k in range(j+1,n):
			Cx = cordx[k]
			Cy = cordy[k]
			ACx= Cx-Ax
			ACy= Cy-Ay
			if abs((ABx*ACy - ACx*ABy)) > 0:
				count +=1
print (count)	

