// 
// File:   vigenere.cc
// Author: cteam03
//
// Created on November 13, 2011, 9:09 AM
//

#include <cstdio>
#include <cstring>

//
// 
//
int main(int argc, char** argv) 
{
    char key [1001];
    
    scanf("%s", key);
    getchar();
    
    while (key[0] != '0')
    {
        int i = 0;
        int len = strlen(key);
        int c = getchar();
        
        for (int j = 0; j < len; j++) key[j] = key[j] - 'A' + 1;
        
        while (c != '\n')
        {
            if (c + key[i] > 'Z')
                printf("%c", c + key[i] - 26);
            else
                printf("%c", c + key[i]);
            
            c = getchar();
            
            i = (i + 1) % len;
        }
        
        printf("\n");
        
        scanf("%s", key);
        getchar();
    }
    
    return 0;
}