#include <bits/stdc++.h>
using namespace std;
int main(){
	int a,b,c,d,e;
	cin>>a;
	e=a%10;
	d=a/10%10;
	c=a/100%10;
	b=a/1000%10;
	a=a/10000%10;
	cout<<e+d+c+b+a; 
}
                  
/**************************************************************
	Problem: 1418
	User: wngjinming
	Language: C++
	Result: Accepted
	Time:12 ms
	Memory:2072 kb
****************************************************************/