Re: 2.2.6_andrea2.bz2

[Pavel Machek <pavel@bug.ucw.cz>]

Hi!

> > Another idea: Currently every bucket in the hash table has to be a
> > linked list. I haven't tried it, but the linked list could be replaced
> > by a tree in order to limit the worst case. Even better, a bucket could
> > stay a linked list as long as only one element is in the bucket (the
> > most common case). I a second element is added, it becomes the root
> > of a tree. Additional elements build the tree. If an element is removed
> > from the tree, the normal tree algorithms apply. If the first element
> > is removed, and there are other elements in the tree, one tree element
> > must be moved to become the new first element.
> 
> this seems expensive and complicated for no good reason.  one can
> construct a simple-to-understand hash function that will have excellent
> average behavior and reasonable worst-case behavior, and even be pretty
> cheap to calculate.  why would i want to go to the expense of

I do not understand. How do you want to guarantee worst-case behaviour
for hash? I think that nearly every hash is going to be linear in
worst case (i.e. everything in one chain).

								Pavel
-- 
I'm really pavel@atrey.karlin.mff.cuni.cz. 	   Pavel
Look at http://atrey.karlin.mff.cuni.cz/~pavel/ ;-).

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