> #include<iostream>
> using namespace std;
> int main()
> {
> 	int n;
> 	while(cin>>n&&n!=0)
> 	{
> 		int s;
> 		s=n%9;
> 		if(s==0)
> 			cout<<"9"<<endl;
> 		else
> 			cout<<s<<endl;
> 	}
> 	return 0;
> }
>