using System;
class Class1
	{
	static void Main(string[] args)
	{
		//vigenere.exe TEXT KEY
		int t,v,s;
		char c;

		t=v=s=0;
		Console.Write("PLAINTEXT:  " + args[0] + "\n");
		Console.Write("CIPHERTEXT: ");
		for(int i=0;i<args[0].Length;i++)
		{
			t=Convert.ToInt16(args[0][i]-65);
			s=Convert.ToInt16(args[1][v]-65);
			t=(t+s) % 26;
			if(++v == args[1].Length)
				v=0;
			
			c=Convert.ToChar(t+65);
			Console.Write(c);
		}
			
	}
}