from collections import defaultdict
from math import gcd
def calc(x,y):
    a = gcd(x,y)
    return (x//a,y//a)

dic = defaultdict(set)
N = int(input())
XY = [list(map(int,input().split())) for _ in range(N)]
XY.sort()
INF = 10 ** 19
for i in range(N-1):
    x0,y0 = XY[i]
    for j in range(i+1,N):
        x1,y1 = XY[j]
        if x0 == x1:
            xim = x0
            xid = 1
            yim = INF
            yid = 1
        elif y0 == y1:
            yim = y0
            yid = 1
            xim = INF
            xid = 1
        else:
            yi = y0 - (y1-y0)/(x1-x0) * x0
            yid = x1 - x0            
            yim = y0 * yid - (y1-y0) * x0
            yim,yid = calc(yim,yid)
            xi = x0 - (x1-x0)/(y1-y0) * y0
            xid = y1 - y0            
            xim = x0 * xid - (x1-x0) * y0
            xim,xid = calc(xim,xid)
        dic[(xim,xid,yim,yid)].add(i)
        dic[(xim,xid,yim,yid)].add(j)
X = [0] * N
for L in dic.values():
    L = sorted(list(L))
    if len(L) == 3:
        X[L[0]] = 1
        X[L[2]] = 1
    if len(L) > 3:
        for l in L:
            X[l] = 1
print(sum(X))