#include <bits/stdc++.h>
using namespace std;
string a, k, b;
char decode[30][30];
int main()
{
	cin >> k >> b;
	int len = k.size();
	for(int i = 0; i < b.size(); i++)
	{
		char c1 = b[i];
		char c2 = k[i % len];
		char c3 = (c1 >= 'A' && c1 <= 'Z') ? 'A' : 'a';
		char c4 = (c2 >= 'A' && c2 <= 'Z') ? 'A' : 'a';
		a[i] = (c1 + (c2 - c4)) % 26 + c3;
	}
	cout << a;
	return 0;
}

样例RE了！