#!/usr/bin/ruby
#coding:utf-8
def egcd(x,y)
	return [x,1,0] if y==0
	g,a,b=egcd(y,x%y)
	[g,b,a-x/y*b]
end

a,b=gets.split.map(&:to_i).sort
if b==0
	gets;p $<.count{|e|
		x,y=e.split.map(&:to_i)
		x==0&&y==0
	}
elsif a==0
	gets;p $<.count{|e|
		x,y=e.split.map(&:to_i)
		x%b==0&&y%b==0
	}
else
	g,z1,z2=egcd(a,b)
	a/=g
	b/=g
	gets;p $<.count{|e|
		x,y=e.split.map{|e|e.to_i.abs}
		next if x%g!=0 || y%g!=0
		x/=g
		y/=g

		#((QQ-PP)n+z2XP+z1XQ-Y)%gcd(2P,2Q)==0
		g0=(2*a).gcd(2*b)
		z=b*b-a*a
		w=z2*x*a+z1*x*b-y
		#zn+w%g0==0
		#zn%g0==-w%g0
		#[-w,z,g0]
		-w%z.gcd(g0)==0
	}
end