pythonize this!

[Alessandro [AkiRoss] Re]

On Jun 15, 1:49 pm, superpollo <ute... at esempio.net> 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)


My functional approach :)

from operator import add
from functools import reduce

def square(l):
  return (v**2 for v in l)

def sign(l, s):
  i = 0
  for v in l:
    yield s[i % len(s)] * v
    i += 1

print reduce(add, sign(square(xrange(1, 2011)), [1, 1, 1, -1, -1]))

(536926141)

~Aki