The statement in the essay (or any essay) "requires space
(and time) exponential in the size of the result" means
the technique should not be used in practice. But if you
are doing proofs, barroom arguments ("can you do it
without looping?") etc., then it should be fine.
----- Original Message -----
From: Alex Giannakopoulos <[email protected]>
Date: Sunday, August 21, 2011 6:21
Subject: Re: [Jprogramming] Finding numbers with _distinct_ digits
To: Programming forum <[email protected]>
> Yes, I was just thinking that, too... as you can use the rows
> with m 1s as
> the combination rows in mCn
> Interesting how many things you can do with #:i.2^ n, it's not
> the first
> time I've used it, either.
>
> I was wondering - since the said essay warns of space and time
> exponentialgrowth - does this mean it's better to use explicit
> loops in such cases?
>
> On 20 August 2011 21:47, Roger Hui <[email protected]> wrote:
>
> > The rows of #:i.2^n contains the information needed
> > to generate m comb n . The combinations essay
> > has this tidbit.
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