Even Fibonacci numbers

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.

Attention: even-valued means the term is even, not even-th

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Idea

iterate, judge, accumulate, done

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def solve(limit):
    def fibonacci():    
        f1, f2 = 0, 1
        while f2 < limit:
            f1, f2 = f2, f1 + f2
            yield f1
    return sum(filter(lambda f: f % 2 == 0, fibonacci()))

solve(4e6)

4613732