#include <iostream>
#include<vector>
using namespace std;

char kodol(int a, int b)
{
 int c;
 c = a+b+1-'A';

 c = (c-int('A')) % ('Z' - 'A' +1 ) + 'A';
 return char(c);
}


int app(istream &f)
{

string key;
string message;



for(;;)
{
  getline(f,key);
  if (key == "0") return 0;
  getline(f,message);
  
  for (unsigned int i=0;i<message.length();i++)
  {
 
    message[i] = kodol(message[i],key[i%key.length()]);

  }

 cout << message << endl;

}

return 0;
}


int main()
{

app(cin);


return 0;
}