#include <bits/stdc++.h>
using namespace std;

int main()
{
	int n,ans=0;
	scanf("%d",&n);
	while (n)  ans+=n%10,n/=10;
	if (ans==1)  ans=10;
	printf("%d",ans);
	return 0;
}

### Prompt

Develop a solution in cpp to the problem described below:

Takahashi has two positive integers A and B.

It is known that A plus B equals N. Find the minimum possible value of "the sum of the digits of A" plus "the sum of the digits of B" (in base 10).

Constraints

* 2 ≤ N ≤ 10^5
* N is an integer.

Input

Input is given from Standard Input in the following format:


N


Output

Print the minimum possible value of "the sum of the digits of A" plus "the sum of the digits of B".

Examples

Input

15


Output

6


Input

100000


Output

10

### Response

```cpp
#include <bits/stdc++.h>
using namespace std;

int main()
{
	int n,ans=0;
	scanf("%d",&n);
	while (n)  ans+=n%10,n/=10;
	if (ans==1)  ans=10;
	printf("%d",ans);
	return 0;
}

```