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Path: utzoo!watmath!clyde!cbosgd!ihnp4!qantel!hplabs!ames!jaw
From: jaw@ames.UUCP (James A. Woods)
Newsgroups: net.news.b
Subject: Re: new algorithm for expire
Message-ID: <1066@ames.UUCP>
Date: Mon, 5-Aug-85 02:50:26 EDT
Article-I.D.: ames.1066
Posted: Mon Aug  5 02:50:26 1985
Date-Received: Tue, 6-Aug-85 11:47:02 EDT
References: <554@down.FUN>
Organization: NASA-Ames Research Center, Mtn. View, CA
Lines: 49


		
#  Fools ignore complexity.  Pragmatists suffer it.
   Some can avoid it.  Geniuses remove it.
	-- Perlis's Programming Proverb #58, SIGPLAN Notices, Sept. l982
.....
		Professor Honeyman's expire nightmare (in one-act)

simpleton:
	why not just do find /usr/spool/news -mtime -14 -exec rm {} \;
	the old-fashioned unix way?
honey: 
	but what about conversations, you dolt?  we need reflexive transitive
	closure for this job -- hmm ... four russians algorithm, no, valiant's
	sub-cubic method, no wait, union-find!  that's it, union-find!

puppy dog undergrad:
	ah professor, you know, even though bell labs tried some of these
	sixth-generation data structures (like hash tables), it's tough
	to grind out sophisticated production code that won't break.  we
	might need more than two credits of independent study for this...
honey:
	nonsense, i might even have something leftover from pathalias.
	[(scratching head) uh well, maybe pathalias does take a few hours to
	regenerate; remind me to work on that so we can play what-if
	games with nsc better].  listen, don't expect to graduate unless you
	understand this algorithm stuff like the back of your hand.  look,
	not only all that crap you learned about huffman codes over in ee
	has been replaced by lempel-ziv, but berkeley does simulated annealing
	in the kernel to get around some tough np-complete register allocation
	probs.  remember, we gotta get cray v8 out of beta test next week.
	just go away.

grad student replacement:
	hey, look at this neato splay tree stuff sleator & tarjan published.
	in pseudo-pascal, even.  my little 9-year-old sister just typed it
	in on her amiga, and it runs rings around union-find. 

honey: 	say what?

9-year old:
	yeah, nice average-case linear behavior, but i had to junk it.
	you're all thinkin' too hard.  i just put horspool's dynamic perfect
	hasher into crontab, and now we expire conversations in one probe!
	don't even need boyer-moore grep to catch false drops.
honey:
	say, where did that simple simon go?

--ames!jaw