James Gray
11/23/2004 11:22:00 PM
(forwarded to Ruby Talk by JEG2)
Begin forwarded message:
> From: Brian Candler <B.Candler@pobox.com>
> Date: November 23, 2004 5:16:20 PM CST
> To: James Edward Gray II <james@grayproductions.net>
> Subject: Re: Ruby quiz suggestion - Countdown
>
> On Tue, Nov 23, 2004 at 08:12:46PM +0000, Brian Candler wrote:
>> There are clearly other optimisations possible. One is to reject any
>> solution for value N using source numbers (a,b,c,d) if we have
>> already seen
>> a solution for N using only a strict subset of (a,b,c,d). But there's
>> a bit
>> of work involved there.
>
> I've not finished yet, but already got it down to 3 seconds :-)
>
> $ time ruby countdown2.rb 926 75 2 8 5 10 10
> Solution: 926=(((75+(8-5))*(10+2))-10)
>
> real 0m3.117s
> user 0m3.025s
> sys 0m0.008s