#include<bits/stdc++.h>
using namespace std;
int main(){
	
	int i,n,s,c;
	cin>>i;
	n=i/10;
	s=i%10;
	c=s+n;
	cout<<c;
	
	return 0;
}
/**************************************************************
	Problem: 1605
	User: huangyaojie3
	Language: C++
	Result: Accepted
	Time:10 ms
	Memory:2072 kb
****************************************************************/