Write one way back when starting Ada 83 (1984).  Based on Djkstra's
algoritm in A Discipline of Programming.  Is this what you want.  (Sorry
for the long delay -- I only get to read CLA once every few weeks when
flying on a plane).  It only does a next perumutation, but a "previous"
permutation is pretty simple to devise.  Use WP's to even prove it :-).
Regards,
Steve Deller


> -----Original Message-----
> From: comp.lang.ada-admin@ada.eu.org 
> [mailto:comp.lang.ada-admin@ada.eu.org] On Behalf Of Hyman Rosen
> Sent: Tuesday, April 30, 2002 11:06 AM
> To: comp.lang.ada@ada.eu.org
> Subject: Re: Generation of permutations
> 
> 
> Ted Dennison wrote:
> > Reinert Korsnes <reinert.korsnes@chello.no> wrote in message 
> > news:<aajce7$7jb$1@snipp.uninett.no>...
> > 
> >>Are there any good (Ada95) packages for generation of permutations
> >>(of elements in array) ?
> > 
> > Sadly, that doesn't come up much...outside of homework assignments. 
> > ;-) Are you writing a bogosort?
> 
> Whether or not it comes up much, in fact the algorithms 
> next_permutation and prev_permutation are part of the C++ 
> standard library. You can find them online in 
<http://www.sgi.com/tech/stl/stl_algo.h>. It should not be too difficult
for the OP to translate them to Ada.

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