N = int(input())
i = 0
while N > 0:
    i += 1
    if 2 ** (i + 1) >= N:
       break
if N == 1:
    print(0)
elif N == 2 ** i:
    print(i)
elif (N - 2 ** i) % 2 == 0:
    print(i + 1)
else:
    print(i + 1)