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


int main()
{
	string n; cin >> n;
	int ans = 0;
	for (int i = 0; i < n.size(); ++i)
		ans += n[i] - 48;
	if (ans == 1) ans = 10;
	cout << ans << endl;
}


### Prompt

Please formulate 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()
{
	string n; cin >> n;
	int ans = 0;
	for (int i = 0; i < n.size(); ++i)
		ans += n[i] - 48;
	if (ans == 1) ans = 10;
	cout << ans << endl;
}


```