euler

fib.py

fib1
=========



	`def fib(a=0, b=1):
    while True:
        yield a
        a, b = b, a + b
sum_ = 0
for f in fib():
    if f > 4000000:
       break
    if f % 2 == 0:
       sum_ += f

print sum_`

fib1.py

def fib(n):
		
		if n == 0:
			return 0
		elif n == 1:
			return 1
		else:
			return fib(n-1) + fib(n-2)