From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (from weis@localhost) by pauillac.inria.fr (8.7.6/8.7.3) id MAA04326 for caml-red; Tue, 10 Oct 2000 12:23:29 +0200 (MET DST) Received: from nez-perce.inria.fr (nez-perce.inria.fr [192.93.2.78]) by pauillac.inria.fr (8.7.6/8.7.3) with ESMTP id XAA12863; Sun, 8 Oct 2000 23:22:01 +0200 (MET DST) Received: from localhost.localdomain (jimbo63.zip.com.au [202.7.88.63]) by nez-perce.inria.fr (8.10.0/8.10.0) with ESMTP id e98LLt124721; Sun, 8 Oct 2000 23:21:56 +0200 (MET DST) Received: from ozemail.com.au (IDENT:root@localhost [127.0.0.1]) by localhost.localdomain (8.9.3/8.8.7) with ESMTP id IAA22902; Mon, 9 Oct 2000 08:26:40 +1100 Message-ID: <39E0E68F.B2786DE7@ozemail.com.au> Date: Mon, 09 Oct 2000 08:26:39 +1100 From: John Max Skaller X-Mailer: Mozilla 4.7 [en] (X11; I; Linux 2.2.12-20 i686) X-Accept-Language: en MIME-Version: 1.0 To: Pierre Weis CC: Xavier Leroy , caml-list@inria.fr Subject: Re: WWW Page of Team PLClub (Re: ICFP programming contest: results) References: <200010070835.KAA28303@pauillac.inria.fr> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: weis@pauillac.inria.fr Pierre Weis wrote: > the body of f. This operation is trivial if you use a conventional > beta reducer, but it is surprisingly difficult if you use De Bruijn > indices. Just out of curiousity, what do you mean by a 'difficult' algorithm? To explain my question in slightly more depth: given some fixed problems with known algorithms, all these algorithms, in the first instance, have equal 'difficulty', namely, 'trivial': if the algorithm is known, it can be implemented. (In general, coding a known algorithm is so easy compared with other programming tasks that I would classify coding by how laborious it is: the only 'difficulty' involved is staying awake long enough to finish the job :-) It is sometimes difficult to _find_ an algorithm for a problem, and one may say that some algorithms are 'inflexible' in the sense that small variations in the problem make finding a solution by considering the 'original' algorithm difficult. It may also be hard to tranform a correct algorithm into a more efficient version. Also, it is clear that some algorithms are difficult to understand. And, some algorithms, coded incorrectly, may be difficult to debug. -- John (Max) Skaller, mailto:skaller@maxtal.com.au 10/1 Toxteth Rd Glebe NSW 2037 Australia voice: 61-2-9660-0850 checkout Vyper http://Vyper.sourceforge.net download Interscript http://Interscript.sourceforge.net