def the_product_of_even(a):
    c = 1
    for i in range(0, len(a), 2):
        c *= a[i]


def sum_(a):
    c, c1 = a.index(0), (a[::-1]).index(0)
    k = 0
    print(c)
    print(c1)
    for i in range(c, len(a) - c1 - 1):
        k += a[i]
    return k


def sort_(a):
    b = []
    for i in a:
        if i >= 0:
            b.append(i)
    for i in a:
        if i < 0:
            b.append(i)
    return b
    #return sorted(a, reverse=True) - можешь так сделать