from math import gcd
import sys
readline = sys.stdin.readline

a,b,c,d = map(int,readline().split())
n = int(input())
xy = [list(map(int,readline().split())) for _ in range(n)]
D = a*d - b*c
if D:
    s = set(((d*x-c*y)%D, (a*y-b*x)%D) for x,y in xy)
    print(len(s))
    exit()
p,q = (gcd(a,c), b//(a//gcd(a,c))) if a else (a//(b//gcd(b,d)), gcd(b,d))
s = set((p*y-q*x,x%p) if p else (p*y-q*x,y%q) for x,y in xy)
print(len(s))