#!/usr/bin/python3

n = int(input())
num_attacks = 1
while True:
    for pattern in range(2**num_attacks):
        damage = 0
        for i in range(num_attacks):
            if pattern % 2 == 0:
                damage += 1
            else:
                damage *= 2
            pattern //= 2
        if damage >= n:
            print(num_attacks)
            break
    else:
        num_attacks += 1
        continue
    break