a, b, c, d  = map(int, input().split())
n = int(input())
XY = []
for i in range(n):
    x, y = map(int, input().split())
    XY.append((x, y))

import math
det = a*d-b*c
S = set()
if det == 0:
    g1 = math.gcd(a, c)
    g2 = math.gcd(b, d)
    for x, y in XY:
        if g1 != 0 and g2 != 0:
            q = min(x//g1, y//g2)
            x = x-q*g1
            y = y-q*g2
            S.add((x, y))
        elif g1 == 0:
            q = y//g2
            y = y-q*g2
            S.add((x, y))
        elif g2 == 0:
            q = x//g1
            x = x-q*g1
            S.add((x, y))
else:
    det = abs(det)
    S = set()
    for x, y in XY:
        z = (d*x-c*y)%det
        w = (-b*x+a*y)%det
        S.add((z, w))
print(len(S))