from random import randint

from functools import reduce


def len_(array):
    return reduce(lambda x, y: x + y, map(lambda x: 1, array))


def enumerate_(array):
    print("I DON'T KNOW")
    return 


def test():
    for _ in range(100):
        array = [randint(-10, 10) for _ in range(randint(5, 5))]
        assert len_(array) == len(array), 'Not really ok'

    print("OK")


if __name__ == '__main__':
    test()