#include<bits/stdc++.h>
using namespace std;
int main(){
	int x,y,n;
	cin>>n;
	x=n%10;
	y=n/10;
	n=x+y;
	cout<<n;
}
/**************************************************************
	Problem: 1605
	User: zengyixuan
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/