#include<stdio.h>

void main(){
	int x,g,s,b,q,w;
	scanf("%d",&x);
	
	b=x/100%10;
	s=x/10%10;
	g=x%10;
	q=x/1000%10;
	w=x/10000%10;
	printf("%d",b+s+g+q+w);	
} 


/**************************************************************
	Problem: 1418
	User: admin
	Language: C
	Result: Accepted
	Time:17 ms
	Memory:1144 kb
****************************************************************/