try:
    import mydebug

    def dprint(*objects):
        print(*objects)
except:
    def dprint(*objects, sep='', end='\n'): pass

# d, p = [int(x) for x in input().split()]
n = int(input())

i = 0
while True:
    if(n <= 2**i):
        break
    i += 1 

print(i)