#include <iostream>
#include <cstdio>
using namespace std;
int main()
{
//int d(int n)
//{
int n;
cin >> n;
int res;
while(n/10 != 0){
res += n % 10;
n /= 10;
}
res += n % 10;
res += n;
//return res;
cout<< res;
return 0;
}
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