#include
int fun(int n)
{int s=0;while(n) {s+=n%10;n=n/10;}
return s;}
main()
{int n;
scanf("%d",&n);
printf("%d\n",fun(n));}
#include
int fun(int n)
{int s=0;while(n) {s+=n%10;n=n/10;}
return s;}
main()
{int n;
scanf("%d",&n);
printf("%d\n",fun(n));}