//team42 (Lukasz Zatorski, Damian Rusak, Krzysztof Piecuch)
#include <cstdlib>
#include <cstdio>
#include <iostream>
#include <vector>
#include <set>
#include <queue>
#include <algorithm>
#include <string>
#include <cstring>
#include <cmath>
#include <ctime>
#include <cassert>
using namespace std;

typedef long long int ll;
typedef pair<int,int> pi;
typedef vector<int> vi;
typedef vector< vi > vii;

#define ft first
#define sd second
#define mp make_pair
#define pb push_back
#define REP(i,a,b) for(register int i = a ; i < b; i++)
#define DOWN(i,a,b) for(register int i = a; i>=b ; i--)
#define WSK(C) typeof((C).begin())
#define FOREACH(wsk, C) for(WSK(C) wsk = (C).begin(); wsk!=(C).end; wsk++)


int main(){
	char c[1002], t[100002];
	while(true){
		scanf("%s", c);
		if(c[0]=='0') return 0;
		scanf("%s", t);
		int sc = strlen(c), st = strlen(t);
		REP(i,0,sc){
			c[i]-='A';	
		}
		int j = 0;
		REP(i,0,st){
			char w = t[i] + 1 + c[j];
			if(w>'Z') w-=26;
			j++;
			if(j==sc) j = 0;
			printf("%c", w);
		}
		printf("\n");
	}
	return 0;
}