def unscatter
      scattered_array = @working_array
      sum_of_digits = scattered_array.inject(:+).to_i
      @working_array = []
      @working_array.tap do |unscatter| 
        10.times do
          unscatter.push scattered_array.pop
          unscatter.rotate! (sum_of_digits ^ spin) * -1
        end
      end
    end
def unscatter
      scattered_array = @working_array
      sum_of_digits = scattered_array.inject(:+).to_i
      @working_array = []
      @working_array.tap do |unscatter| 
        10.times do
          unscatter.push scattered_array.pop
          unscatter.rotate! (sum_of_digits ^ spin) * -1
        end
      end
    end
Reverse the scatter