From: Heesob Park <phasis@...>
Date: 2008-09-05T15:02:49+09:00
Subject: Re: Need a 40 LOC (ignoring comments) to be shorter -- suggestions wanted

2008/9/5 RichardOnRails <RichardDummyMailbox58407@uscomputergurus.com>:
> Hi All,
>
> My middle-school granddaughter posed the following challenge to me:
>
> Within 10 minutes, Use the digits 3 to 7 in any order
> to form a three-digit multiplicand and a two-digit multiplier
> such that their product is minimal.
>
> Out of curiosity as to whether my guess was right,
> and with a view toward eliciting an interest in her
> for Ruby programming,  I wrote the program posted at
> http://www.pastie.org/266447
>
> The program reveals that I was wrong, but it took me about 40 lines of
> code,
> ignoring comments.  That would probably overwhelm her.  I was hoping
> that
> the code could be condensed with Ruby-isms.  BTW, I left some put's in
> there
> intended to give her a sense of the programs functionality.
>
> Any ideas/suggestions?
>
Here is a simple and stupid solution.

 a = [3,4,5,6,7]
 d = {}
 (a[0,3].to_s.to_i .. a.reverse[0,3].to_s.to_i).each{|i|
   (a[0,2].to_s.to_i .. a.reverse[0,2].to_s.to_i).each{|j|
     d[[i,j]]=i*j if a.to_s==((i.to_s+j.to_s).split(//).sort.to_s)
   }
 }
 p d.sort{|a,b| a[1]<=>b[1]}[0]


Regards,

Park Heesob