-- table x,y,z
 function w(x,y,z)
 	c="black"
 	if z<0 then c="red" end
 	return c
 end
 
 n=1
 y=0
 for x = -n, n do
  for z = -n, n do
  --print(x,y,z)
    c=w(x,y,z)
    print( string.format("%3d %2d %2d %s", x,y,z, c) )
  end
end