Can you explain please what this decorator do?

building memo is the same as using lru_cache so...

Oh, I see, thanks.

My bad. Didn't see it was already running on python 3.x. :)

I'd use xrange instead of range for range creates a list full with the numbers in the range you specified before using them while xrange evaluates lazily or something like that, therefore xrange is usually faster. Not a big deal on this kata but a thing to consider on bigger iterations/projects.

http://stackoverflow.com/questions/135041/should-you-always-favor-xrange-over-range

http://vairoj.com/2010/04/replace-python-range-with-xrange-for-speed.html

Note: Apparently this only applies to python 2.x as xrange has been removed from python 3.x and range now acts as xrange.

my easy python 101 code for the non-mathematician...

@gambith The method implemented by Zantyr and me allows for much larger values of n without overflowing.

What about?:

def fibElem(N):
q = (5**(1.0/2) + 1) / 2
temp = 1
for i in range(N - 2):
temp = int(temp * q + 0.5)
return temp

N is Natural number.

Fabulous - I can't understand anything though! XD