nullteiler.rb

menge = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
menge.each do |x|
  if x != 0 then
    menge.each do |y|
      if y != 0 then
        if ((x * y) % menge.length == 0) then
          print x.to_s + " * " + y.to_s + " % " + menge.length.to_s + " = 0\n"
        end
      end
    end
  end
end