#!/usr/bin/ python3.8
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
import numpy as np

N = int(readline())
XY = np.array(read().split(), np.int64)
X = XY[::2]
Y = XY[1::2]
g = np.abs(np.gcd(X, Y))
Xd = X // g
Yd = Y // g
key = (Xd << 32) + Yd

total = N * (N - 1) * (N - 2) // 6
ng0 = 0
ng1 = 0
ng2 = 0
ng3 = 0
for x, y, k in zip(X, Y, key):
    n = np.count_nonzero(X * y - Y * x > 0)
    same = np.count_nonzero(key == k)
    opp = np.count_nonzero(key == -k)
    ng0 += n * (n - 1) // 2
    ng1 += (same - 1) * n
    ng2 += opp * (N - same - opp)
    ng3 += (same - 1) * opp

ng = ng0 + (ng1 + ng2 + ng3) // 2

print(total - ng)