#include<bits/stdc++.h>
using namespace std;
string s,k;
char n;
int lk,ls,a;
int main(){
	cin>>k>>s;
	lk = k.length();
	ls = s.length();
	for(int i=0;i<lk;i++)
		if(k[i]>='a' && k[i]<='z') k[i]-=' ';
	for(int i=0;i<ls;i++){
		if(a>=lk) a=0;
		n = s[i] - (k[a]-'A');
		if(n<65 && s[i]>='A' && k[i]<='Z') n+=26;
		else if(n<97 && s[i]>='a' && k[i]<='z') n+=26;
		s[i] = n;
		a++;
	}
	cout<<s;
	return 0; 
}