#! ruby
# yukicoder My Practice
# author: Leonardone @ NEETSDKASU

def gs(); gets.chomp; end
def gi(); gets.to_i; end
def gss(); gets.chomp.split; end
def gis(); gss.map(&:to_i); end

# 解説読後
# http://yukicoder.me/problems/849/editorial

P, Q = gis
N = gi

g = P * Q == 0 ? 1 : P.gcd(Q)

c = 0

N.times do
    x, y = gis.map(&:abs)
    
    if P == 0 && Q == 0
        c += 1 if x == 0 && y == 0
        next
    end
    if P == 0
        c += 1 if x % Q == 0 && y % Q == 0
        next
    end
    if Q == 0
        c += 1 if x % P == 0 && y % P == 0
        next
    end
    
    x /= g
    y /= g
    
    u, v = [x % 2, y % 2].minmax
    
    if u == 0 && v == 1
        c += 1 if P % 2 == 0 || Q % 2 == 0
    else
        c += 1
    end
    
end

p c