#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
char k[110],c[1010];
int ke[110];
int main()
{
    scanf("%s%s",k,c);
    int len=strlen(k);
    for(int i=0;i<len;i++){
        if('A'<=k[i]&&k[i]<='Z')ke[i]=k[i]-'A';
        else ke[i]=k[i]-'a';
    }
    for(int i=0;i<strlen(c);i++){
        if('A'<=c[i]&&c[i]<='Z'&&c[i]-ke[i%len]<'A')c[i]+=26;
        else if('a'<=c[i]&&c[i]<='z'&&c[i]-ke[i%len]<'a')c[i]+=26;
        c[i]-=ke[i%len];
        printf("%c",c[i]);
    }
    return 0;
}