using System;
class Program
{
    static void Main(string[] args)
    {
        int n = int.Parse(Console.ReadLine());
        Console.WriteLine(new string('.', n + 1) + new string('_', 2 * n + 1) + new string('.', n + 1));
        for (int i = 0; i <= n; i++)
        {
            if (i < n)
            {
                Console.WriteLine(new string('.', n - i) + "//" + new string('_', 2 * n - 1 + 2 * i) + "\\\\" + new string('.', n - i));
            }
            else
            {
                Console.WriteLine("//" + new string('_', n + i - 3) + "STOP!" + new string('_', n + i - 3) + "\\\\");
            }
        }
        for (int i = n; i > 0; i--)
        {
            Console.WriteLine(new string('.', n - i) + "\\\\" + new string('_', 2 * n - 1 + 2 * i) + "//" + new string('.', n - i));
        }
    }
}