namespace XORenc
{
    using System;
    using System.Linq;

    class Program
    {
        static void Main()
        {
            var a = Console.ReadLine(); // Read text to cypher
            var key = Console.ReadLine()[0]; // Read key character
            var encoded = a.Select(x => (byte)(x ^ key)).ToArray(); // Encode text
            Console.WriteLine(Convert.ToBase64String(encoded)); // Write result as Base64
        }
    }
}