c,g=p~-$<.read.split(?\n).count{|s|x,y=s.split.map &:to_i;g ?y&&(g>0?x%g<1&&y%g<1&&(x-y)*c/g%2<1:x*x+y*y<1):(1>g=x.gcd(y))||c=x*y/g/g%2}