pythonize this!

[superpollo]

Stefan Behnel ha scritto:
> superpollo, 15.06.2010 14:55:
>> Peter Otten ha scritto:
>>> superpollo wrote:
>>>
>>>> goal (from e.c.m.): evaluate
>>>> 1^2+2^2+3^2-4^2-5^2+6^2+7^2+8^2-9^2-10^2+...-2010^2, where each three
>>>> consecutive + must be followed by two - (^ meaning ** in this context)
>>>
>>>>>> from itertools import cycle, izip
>>>>>> sum(sign*i*i for sign, i in izip(cycle([1]*3+[-1]*2), range(1, 
>>>>>> 2011)))
>>> 536926141
>>
>> don't understand it bit i like this a lot!
> 
> Didn't you want to get it "pythonized"? If it's not understandable, it 
> can't be pythonic.

maybe i must study itertools then ;-)

thanks

bye