int sum(int a)
{
int s=0;
while(a!=0){
s+=a%10;
a=a/10;
}
return s;
}
int main()
{
int x;
scanf("%d",&x);
printf("%d",sum(x));
return 0;
}
int sum(int a)
{
int s=0;
while(a!=0){
s+=a%10;
a=a/10;
}
return s;
}
int main()
{
int x;
scanf("%d",&x);
printf("%d",sum(x));
return 0;
}