Question
Remaining Odd Count
In a magical land, you discover an ancient scroll that reveals a secret about the first N odd numbers: A = {1, 3, ... , 2N - 1}. To unlock the wisdom of this scroll, you must enhance each number in the array by a special value X, which represents the count of integers from 1 to N that can divide each number's position i (using 1-based indexing). After performing this enchanting operation, your quest is to find out how many odd numbers remain in the array.
Input
The first line of the input contains a single integer N.
Constraints:
1 ≤ N ≤ 1018
Constraints:
1 ≤ N ≤ 1018
Output
Print the number of odd numbers that are present in the array after performing all the operations.
Example
Sample Input
4
Sample Output
2
Explanation
First four odd numbers are: 1, 3, 5, 7.
The indices 1, 2, 3, and 4 are divided by 1, 2, 2, and 3 numbers respectively.
Adding these values in given numbers, we will get 2, 5, 7, and 10. Thus, only two numbers remain odd after performing the given operation.
4
Sample Output
2
Explanation
First four odd numbers are: 1, 3, 5, 7.
The indices 1, 2, 3, and 4 are divided by 1, 2, 2, and 3 numbers respectively.
Adding these values in given numbers, we will get 2, 5, 7, and 10. Thus, only two numbers remain odd after performing the given operation.