tijie

#include<bits/stdc++.h>
using namespace std;
int main() {
	string s1, s2;
    cin >> s1 >> s2;
    string s;
    int i = s1.size() - 1;
    int j = s2.size() - 1;
    int x = 0;
    while (i >= 0 || j >= 0 || x > 0) {
        int n1 = (i >= 0) ? s1[i] - 'A' : 0;
        int n2 = (j >= 0) ? s2[j] - 'A' : 0;
        int sum = n1 + n2 + x;
        x = sum / 20;
        int r = sum % 20;
        s = char(r + 'A') + s;
        i--, j--;
    }
    while(s[0] == 'A') s.erase(0, 1);
    cout << s << endl;
	return 0;
}