# File utilities/structures.rb, line 222
  def heapify i
    l = left i
    r = right i
    if (l <= @size) and (@keys[l] < @keys[i]) then
      smallest = l
    else
      smallest = i
    end
    if (r <= @size) and (@keys[r] < @keys[smallest]) then
      smallest = r
    end
    if smallest != i then
      temp = @keys[i]
      @keys[i] = @keys[smallest]
      @keys[smallest] = temp
      temp = @objects[i]
      @objects[i] = @objects[smallest]
      @objects[smallest] = temp
      heapify smallest
    end
  end