using System;

public class Program
{
    public static void Main()
    {
        string meta = Console.ReadLine();
        string[] arr = meta.Split();
        string letter = arr[0];
        sbyte number = sbyte.Parse(arr[1]);

        if (number < 3 || number > 100) Console.WriteLine("zla wartosc");
        else if (letter == "B")
        {
            GeneratePatternB(number);
        }
        else if (letter == "A")
        {
            sbyte secondParametr = sbyte.Parse(arr[2]);
            GeneratePatternA(number, secondParametr);
        }
    }

    public static void GeneratePatternA(sbyte number, sbyte secondParametr)
    {
        int fristParam = number % 2 == 0 ? number + 1 : number;
        int secondParam = secondParametr % 2 == 0 ? secondParametr + 1 : secondParametr;

        for (int i = 0; i < secondParam; i++)
        {
            for (int j = 0; j < fristParam; j++)
            {
                if (i == 0 || i == fristParam || i % 3 == 0) Console.Write("*");
                else if (j == 0 || j % 4 == 0) Console.Write("*");
                else Console.Write(".");
            }
            Console.WriteLine();
        }
    }

    public static void GeneratePatternB(sbyte number)
    {
        for (int i = 1; i <= number; i++)
        {
            for (int j = 1; j <= number; j++)
            {
                if (i == 1 || i == number) Console.Write("*");
                else if (i == j) Console.Write("*");
                else Console.Write(".");
            }
            Console.WriteLine();
        }
    }
}