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Date: Tue, 23 Oct 2012 00:04:23 -0400
From: Phil Hobbs <pcdhSpamMeSensel...@electrooptical.net>
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Subject: Re: numerical challenge
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On 10/22/2012 11:36 PM, RichD wrote:
> On Oct 22,  Phil Hobbs <pcdhSpamMeSensel...@electrooptical.net> wrote:
>>> I saw this posed as an interview question:
>>> (usual exponent notation)
>>> What are the last 3 digits of 171 ^ 172?
>>
>>> Presumably, one is given pen and paper.
>>> Is there a trick here?  The second digit isn't too tough,
>>> but the third is a lot of work.
>>
>> If you interpret it in C, 171 XOR 172, it's not that hard:
>>
>> 171 = 160+11 = 0xAB
>> 172 = 160+12 = 0xAC
>>
>> 0xB = 0b1011
>> 0xA = 0b1010
>> so 171 ^ 172 = 1.
>
> huh?
>
>> If you interpret it as taking the 172nd power of 171, you could be there
>> awhile.
>
> I think you flunked the interiew.
>
> --
> Rich
>

I'm glad about that.  I prefer working on fun stuff, of which I have 
lots at the moment.

Cheers

Phil Hobbs

-- 
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510 USA
+1 845 480 2058

hobbs at electrooptical dot net
http://electrooptical.net