Problem Description
In many programming algorithms, 'log n' is a common term in its complexity analysis. What does 'log n' mean? In the context of programming algorithms, it means "log n to the base of 2".
So what is 'log'? 'log base 2' means how many times a number can be divided by 2. 'log base 3' means how many times a number can be divided by 3.. and so on. (Eg log2 8 = 3, log3 9 = 2).
Your task is to find out how many times a number can be divided (using integer division) by 2 before it is less than 2.
Input
Consists a single integer, which is not more than 1000000000.
Output
A single integer, which is how many times a number can be divided by 2 before it is less than 2.
Sample Input
3
Sample Output
1