#include <iostream>
using namespace std;

int main() {
    int n;
    cin >> n;
    int sum = n / 10 + n % 10;
    cout << sum << endl;
    return 0;
}    
/**************************************************************
	Problem: 1605
	User: fuyijun
	Language: C++
	Result: Accepted
	Time:6 ms
	Memory:2072 kb
****************************************************************/