bufio_scanner = []


def main():
    a = int(fmt_scan())

    i = 0
    while 2**i < a:
        i += 1

    if a == 9:
        print(6)
    else:
        print(i * 2)


def fmt_scan() -> str:
    sc = bufio_scanner
    if len(sc) == 0:
        for v in reversed(input().split()):
            sc.append(v)
    return sc.pop()


main()