import sys

sys.setrecursionlimit(10**6)
int1 = lambda x: int(x)-1
p2D = lambda x: print(*x, sep="\n")
def II(): return int(sys.stdin.buffer.readline())
def LI(): return list(map(int, sys.stdin.buffer.readline().split()))
def LI1(): return list(map(int1, sys.stdin.buffer.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def BI(): return sys.stdin.buffer.readline().rstrip()
def SI(): return sys.stdin.buffer.readline().rstrip().decode()
# dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
inf = 10**16
md = 998244353
# md = 10**9+7

from math import atan2
from bisect import *

n=II()
xy=LLI(n)

rxy=[(atan2(y,x),x,y) for x,y in xy]
rr=[r for r,x,y in rxy]
rxy.sort(key=lambda x:x[0])
rr.sort()
# print(rxy)
# print(rr)

def rev(i):
    r,x,y=rxy[i]
    return atan2(-y,-x),-x,-y

ans=0
for j in range(n):
    for i in range(j):
        r1,x1,y1=rev(i)
        r2,x2,y2=rev(j)
        s=x1*y2-y1*x2
        if s==0:continue
        if s<0:r1,r2=r2,r1
        l=bisect_right(rr,r1)
        r=bisect_left(rr,r2)
        if l<=r:ans+=r-l
        else:ans+=n-l+r
        # print(i,j,l,r,ans)

print(ans//3)