#!/usr/local/bin/ruby
class Array
  def randomize
    new_arr = []
    until self.empty?
      x = self.choice
      new_arr << x
      self.delete x
    end
    return new_arr
  end
  
  def randomize!
    self.replace(self.randomize)
  end
end

arr = [2, 3, 5, 7, 11, 13, 17, 19]
puts arr.join(", ")
arr.randomize!
puts arr.join(", ")