#Each new term in the Fibonacci sequence is generated by adding the previous 
#two terms. By starting with 1 and 2, the first 10 terms will be:

#	1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...

#By considering the terms in the Fibonacci sequence whose values do not exceed
#four million, find the sum of the even-valued terms.'''

sum,t1,t2 =0,1,2
while t2 < 4000000:
	if t2 % 2 ==0:
		sum += t2
	t1, t2 = t2, t1 + t2

print sum	
