problem2-thegezy.py

'''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, 144, ...

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

def Fibonacci(x):               #function to generate the Fibonnaci sequence
    a, b = 1, 2                 #initial terms: 1 and 2
    while (a < x):
        yield a
        a, b = b, a+b           #swap values, add to get the next term

print ("The even terms of the Fibonacci sequence less than 4,000,000 are:")
s = 0                           #initial sum declared
for y in Fibonacci(4000000):    #function call
    if (y % 2 == 0):            #get the even-valued terms
        s += y                  #increment the sum
        print (y)               #print the terms
print ("And their sum is ", s)  #print the sum