namespace Stop
{
    using System;

    public class Stop
    {
        public static void Main()
        {
            int n = int.Parse(Console.ReadLine());
            Console.WriteLine(
                "{0}{1}{0}",
                new string('.', n + 1),
                new string('_', (n * 2) + 1));
            for (int i = 0, j = n; i < n; i++, j--)
            {
                Console.WriteLine(
                    "{0}//{1}\\\\{0}",
                    new string('.', j),
                    new string('_', n * 2 - 1 + (i * 2)));
            }

            Console.WriteLine("//{0}STOP!{0}\\\\", new string('_', (n * 2) - 3));
            for (int i = 0, j = n; i < n; i++, j--)
            {
                Console.WriteLine(
                    "{0}\\\\{1}//{0}",
                    new string('.', i),
                    new string('_', n * 2 - 1 + (j * 2)));
            }
        }
    }
}