The number in question, 2147483648, is a power 
of 2 and so can be readily solved by hand.
Raul and Andrew have already shown two solutions.
It's not too hard to show that there are no other ones.



----- Original Message -----
From: Dan Bron <[email protected]>
Date: Friday, July 24, 2009 16:37
Subject: Re: [Jprogramming] 2147483648
To: Programming forum <[email protected]>

> Eugene wrote:
> >  there is an answer.
> 
> It would be an interesting exercise to build a J verb that 
> produced all the
> possible J constants up to a given length.  
> 
> Another approach would be to generate all possible strings up to 
> a given
> length, containing J only constant characters, and then reduce 
> these to
> valid J constants.  But this approach doesn't really scale 
> well.  
> 
> For example, reading DoJ parts I & Constants, it seems like this 
> is the
> valid universe of J constant characters:
> 
>            jcc 
> =. '_.',DIGITS,LCALPHA
> 
> and to test for even a modest, 1 character improvement to Raul's 
> solution:
>            #jcc
>       38
>            (#jcc)^7x
>       114415582592
> 
> would involve ~115 billion possibilities.
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