performance problem in python 2.2
Gerhard Häring
gerhard.haering at gmx.de
Fri Jul 26 21:40:20 EDT 2002
* Paul Rubin <phr-n2002b at NOSPAMnightsong.com> [2002-07-26 18:13 -0700]:
> Jeff Davis <jdavis at empires.org> writes:
>
> > If you read my C code, you'll see that I used the 'unsigned long long type'
> > which is a 64-bit int. And I only stored 2^32 in it. When I needed to
> > crunch the numbers, I treated 2^64 as p*p (because 2^64 ==
> > sqrt(2^64)*sqrt(2^64) == 2^32*2^32), and then I commuted the
> > multiplication so it would happen in a way that wouldn't overflow.
>
> Oh whoops, yes, I missed that. "Long long" is not part of standard C,
It is. C99.
Gerhard
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reduce(lambda x,y:x+y,map(lambda x:chr(ord(x)^42),tuple('zS^BED\nX_FOY\x0b')))
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