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FromRoland Kuhn <>
SubjectRe: [RFC] div64_64 support
DateTue, 6 Mar 2007 16:10:08 +0100
Hi Andi!

On 6 Mar 2007, at 15:45, Andi Kleen wrote:

>> <rant>
>> Let me see... You throw code like that and expect someone to actually
>> understand it in one year, and be able to correct a bug ?
>
> To be honest I don't expect any bugs in this function.
>
>> </rant>
>>
>> Please add something, an URL or even better a nice explanation,
>> per favor...
>
> It's straight out of Hacker's delight which is referenced in the
> commit
> log.
>
And it's pretty neat, too. Hint: (y+1)**3 = y**3 + 3*y**2 + 3*y + 1.
The algorithm is exactly the same as for calculating the cubic root
on paper, digit by digit. I found that algo in the school notebook of
my grandpa (late 1920ies), a pity that it's not taught anymore...
pocket calculators _do_ have downsides ;-)

Ciao,
Roland

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-----BEGIN GEEK CODE BLOCK-----
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