#include<bits/stdc++.h>
using namespace std;
int main(){
    int i,a,b,c,d,e;
    cin>>i;
    a=i%10;
    b=i/10%10;
    c=i/100%10;
    d=i/1000%10;
    e=i/10000%10;
    cout<<a+b+c+d+e;
}
/**************************************************************
	Problem: 1418
	User: wuzhijing
	Language: C++
	Result: Accepted
	Time:14 ms
	Memory:2072 kb
****************************************************************/