On Jul 26, 2005, at 2:21 PM, Dominik Bathon wrote:

>>>>     def extract(  )
>>>>         extracted = @heap[1]
>>>>         @heap[1] = @heap.pop unless @heap.size.zero?
>>>>         sift_down
>>>>         extracted
>>>>     end
>>>>
>>>>
>>>
>>> This doesn't really extract the last element...
>>>
>>
>> Can you please show a failing example?  I tried to find one and  
>> couldn't.
>>
>
> Maybe I havn't been clear enough, I meant the heap can't get empty,  
> you can't remove the last remaining element:

Got it.  Thanks for the lesson Dominik!

James Edward Gray II