#include<bits/stdc++.h>
#define maxn 100005

using namespace std;
int s[maxn],ans,n;
int main(){
    cin >> n; ans=123456;
    for (int i=1;i<=100000;i++) s[i]=s[i/10]+i%10;
    for (int i=1;i<n;i++) ans=min(ans,s[i]+s[n-i]);
    cout << ans << endl;
}

### Prompt

Please create a solution in Cpp 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>
#define maxn 100005

using namespace std;
int s[maxn],ans,n;
int main(){
    cin >> n; ans=123456;
    for (int i=1;i<=100000;i++) s[i]=s[i/10]+i%10;
    for (int i=1;i<n;i++) ans=min(ans,s[i]+s[n-i]);
    cout << ans << endl;
}

```