using System;
class Class1
{
	static void Main(string[] args)
	{
		int t;
		char c;
		Console.Write("Plaintext:  " + args[0] + "\n");
		Console.Write("Ciphertext: ");
		for(int i=0;i<args[0].Length;i++)
		{
			t=System.Convert.ToInt16(args[0][i]-65);
			t = (t * Convert.ToInt16(args[1])) % 26;
			t = (t + Convert.ToInt16(args[2])) % 26;
			c=Convert.ToChar(t+65);	
			Console.Write(c);
		}
	}
}