The problem:

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

My solution (in python):

# Author: Will Clausen # # Date: Jan 6, 2013 # # This program will solve problem 2 in Project # Euler. # This function generates the fibonacci numbers # under 4,000,000, sums the even ones, and returns # the sum. Simple. def problem2(): f1 = 1 f2 = 2 fn = 0 sum = 2 while fn < 4000000: fn = f1 + f2 f1 = f2 f2 = fn if fn % 2 == 0: sum += fn return sum