text: import math
  def mod(x, y):
      return x - y * math.trunc(x / y)
  
  
  
  a = 1
  b = 2
  sum = 0
  while a < 4000000:
      if mod(a, 2) == 0:
          sum += a
      c = a
      a = b
      b += c
  print("%d\n" % sum, end='')
  
  