N21_innovate

def f(s, cnt):
    if s >= 43 and cnt - 1 == 2:
        return 1
    if s >= 43 and cnt - 1 < 2:
        return 0
    if s < 43 and cnt - 1 == 2:
        return 0

    A = f(s + 1, cnt + 1)
    B = f(s * 3, cnt + 1)
    C = f(s + 4, cnt + 1)

    if cnt % 2 == 1:
        return A and B and C
    else:
        return A or B or C

for s in range(1, 43):
    A = s + 1 <= 42 and ( (s + 1) * 3 >= 43 or f(s + 1, 0) )
    B = s + 4 <= 42 and ( (s + 4) * 3 >= 43 or f(s + 4, 0) )
    C = s * 3 <= 42 and ( s * 9 >= 43 or f(s * 3, 0) )

    if A and B and C:
        print(s)
        break