#include<bits/stdc++.h>
using namespace std;
int main(){
	int a;
	cin>>a;
	int w=a/10000;
	int q=a/1000%10;
	int b=a/100%10;
	int s=a/10%10;
	int g=a%10;
	cout<<g+s+b+q+w;
	return 0;
}
/**************************************************************
	Problem: 1418
	User: chenjingqi
	Language: C++
	Result: Accepted
	Time:12 ms
	Memory:2072 kb
****************************************************************/