Problem 2

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.

a=1
b=2
c=a+b
result=2;
while c<4000000:
    a=b
    b=c
    c=a+b
    if c%2==0:
        result+=c
print(result)

输出结果： 4613732

用时：小于1s