#include<bits/stdc++.h>
using namespace std;
int main(){
    int n=0,a,b,c,d,e;
    cin>>n;
    a=n%10;
    b=n/10%10;
    c=n/100%10;
    d=n/1000%10;
    e=n/10000;
    cout<<a+b+c+d+e;
    return 0;
}
/**************************************************************
	Problem: 1418
	User: panjinyan
	Language: C++
	Result: Accepted
	Time:14 ms
	Memory:2072 kb
****************************************************************/