using System;

class Program
{
    static void Main()
    {
        int n = int.Parse(Console.ReadLine());
        Console.WriteLine("{0}{1}{0}", new string('.', n + 1), new string('_', 2 * n + 1));
        int a = 2 * n - 1;
        for (int i = n; i >= 1; i--)
        {
            Console.WriteLine("{0}//{1}\\\\{0}", new string('.', i), new string('_', a));
            a += 2;
        }
        a = n * 2 - 3;
        Console.WriteLine("//{0}STOP!{0}\\\\", new string('_', a));
        a = 4 * n - 1;
        for (int i = 0; i < n; i++)
        {
            Console.WriteLine("{0}\\\\{1}//{0}", new string('.', i), new string('_', a));
            a -= 2;
        }
    }
}