Solve the programming task below in a Python markdown code block.
Snuke received a positive integer N from Takahashi. A positive integer m is called a favorite number when the following condition is satisfied:

* The quotient and remainder of N divided by m are equal, that is, \lfloor \frac{N}{m} \rfloor = N \bmod m holds.



Find all favorite numbers and print the sum of those.

Constraints

* All values in input are integers.
* 1 \leq N \leq 10^{12}

Input

Input is given from Standard Input in the following format:


N


Output

Print the answer.

Examples

Input

8


Output

10


Input

1000000000000


Output

2499686339916