// Code From http://www.codecodex.com
    def bubble_sort(list)  
      list = list.dup   # we should not modify original list  
      for i in 0...list.length  
        for j in 0..(list.length - i - 2)  
          list[j], list[j + 1] = list[j + 1], list[j]  if list[j + 1] < list[j]  
        end  
      end  
      return list  
    end