#!/usr/bin/python
# Copyright 2010 P. Wilczynski
# Project Euler
# Problem Number 2

import sys
import re

"""
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, ...

Find the sum of all the even-valued terms in
the sequence which do not exceed four million.

"""


def fib_sum(max):
  i = 1
  i_prev = 0
  sum = 0
  while (i<=max):
    print i, i_prev
    
    i += i_prev
    i_prev = i - i_prev
    if i%2==0:
      sum += i
  print "The sum is: ", sum

def main():
  max = int(sys.argv[1])
  fib_sum(max)



if __name__ == '__main__':
  main()
