using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace StopSign
{
    class Program
    {
        static void Main(string[] args)
        {

            int n = int.Parse(Console.ReadLine());

            Console.WriteLine("{0}{1}{0}", new string('.', n+1), new string('_', 2*n+1));

            for (int i = 0; i < n; i++)
            {
                Console.WriteLine("{0}{1}{2}{3}{0}", new string('.', n-i), "//", new string('_',(2*i) + n*2-1), "\\\\");
            }
            // total width = 4*n + 3
            // underscore num = ((4*n+3)-9)/2
            Console.WriteLine("{0}{1}{2}{1}{3}", "//", new string('_',n*2-3 ), "STOP!", "\\\\");

            for (int i = 0; i < n; i++)
            {
                Console.WriteLine("{0}{1}{2}{3}{0}", new string('.', i), "\\\\", new string('_', 4*n-1-2*i), "//");
            }

        }


    }
}