Problem Statement

Takahashi is growing a plant. Its height at the time of germination is 0$,\mathrm{cm}.$0, its height increases by 2^i$,\mathrm{cm} day i$'$s night (0 \le i)$.
Takahashi's height is H$,\mathrm{cm}$.
Every morning, Takahashi measures his height against this plant. Find the first day such that the plant's height is strictly greater than Takahashi's height in the morning.

Input

The input is given from Standard Input in the following format:
H

Output

Print an integer representing the first day such that the plant's height is greater than Takahashi's height in the morning.

Constraints

• $1 \leq H \leq 10^{9}$
• All input values are integers.

Sample Input 1

54

Sample Output 1

6

The plant's height in the mornings of days 1, 2, 3, 4, 5, 6 will be 1$,\mathrm{cm}, 3$$,\mathrm{cm}, 7$$,\mathrm{cm}, 15$$,\mathrm{cm}, 31$$,\mathrm{cm}, 63$$,\mathrm{cm},$ respectively. The plant becomes taller than Takahashi in the morning day 6, so print 6.

Sample Input 2

7

Sample Output 2

4

The plant's height will be 7$,\mathrm{cm}$3 and 15$,\mathrm{cm}$ in the morning day 4. The plant becomes taller than Takahashi in the morning of day 4, so print 4. Note that, in the morning of day 3, the plant is as tall as Takahashi, but not taller.

Sample Input 3

262144

Sample Output 3

19

见题面 Input 部分

见题面 Output 部分