#include<bits/stdc++.h>

using namespace std;

int main()
{
	int n;
	cin >> n;
	int a = 0; 
	while(n > 0){
		a += n % 10;
		n /= 10;
	}
	if(a == 1){
		a = 10;
	}
	cout << a;
	return 0;
}

### Prompt

Your task is to create a cpp solution to the following problem:

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;
	cin >> n;
	int a = 0; 
	while(n > 0){
		a += n % 10;
		n /= 10;
	}
	if(a == 1){
		a = 10;
	}
	cout << a;
	return 0;
}

```