#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <utility>
#include <stack>
#include <vector>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <list>

#define SIZEOF(a) (sizeof(a)/sizeof(a[0]))
#define FILL(a, b) fill (a,a+SIZEOF(a),b)
#define FOR(a,b,c) for(int a=b; a<=c; a++)
#define FORARR(i,a) for(usigned i=0; i<SIZEOF(a); i++)
#define FOREACH(a,b) for(__typeof((b).begin()) a=(b).begin(); a!=(b).end(); a++)
#define GETI(a) scanf("%d", &a)

using namespace std;

int main(void) {

	string key;
	while (getline(cin, key) && key != "0") {
		string text;
		getline(cin, text);
		int textlen = text.length();
		int keylen = key.length();
		FOR(i,0,textlen-1) {
			text[i] = (text[i]-'A' + (key[i%keylen]-'A'+1)) % 26 + 'A';
		}
		cout << text << endl;
	}
	

	return 0;

}