Re: What´s the algorithm that compresses a 20 digit big int, into 8 bytes ?
From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Fri, 09 Apr 2010 14:18:03 -0300
Message-ID: <4bbf6154$0$12418$9a566e8b_at_news.aliant.net>
>
> Any proof of that, or is it just another hypothesis ? My intuition
> tells me this is true, but I would like to see a proof of that.
Date: Fri, 09 Apr 2010 14:18:03 -0300
Message-ID: <4bbf6154$0$12418$9a566e8b_at_news.aliant.net>
> On Apr 9, 11:45 am, Bob Badour <bbad..._at_pei.sympatico.ca> wrote:
>
>>If it support the full 20 decimal digit range, no algorithm will fit it >>into 64 bits so choosing a different algorithm will achieve nothing.
>
> Any proof of that, or is it just another hypothesis ? My intuition
> tells me this is true, but I would like to see a proof of that.
The proof is trivial. 20 decimal digits have 10^20 distinct values. 64
binary digits have 2^64 distinct values.
10^20 > 2^64 > 10^19