import sys
from math import gcd
def I(): return int(sys.stdin.readline().rstrip())
def MI(): return map(int,sys.stdin.readline().rstrip().split())


P,Q = MI()
g = gcd(P,Q)

N = I()
ans = 0
for _ in range(N):
    X,Y = MI()
    if g == 0:
        if X == Y == 0:
            ans += 1
        continue
    if X % g == Y % g == 0:
        if (P//g+Q//g) % 2 == 0:
            if (X//g+Y//g) % 2 == 0:
                ans += 1
        else:
            ans += 1

print(ans)