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

namespace _03.Task
{
    class Program
    {
        static void Main(string[] args)
        {
            int n = int.Parse(Console.ReadLine());
            int width = (n + n) - 1;
            int freeSpace = n - 1;
            int slash = n - 2;
            int x = 0;
            Console.Write(new string(' ', freeSpace));
            Console.Write(new string(':', n));
            Console.WriteLine();
            freeSpace--;
            for (int i = 0; i < n - 2; i++)
            {
                Console.Write(new string(' ', freeSpace));
                Console.Write(new string(':', 1));
                Console.Write(new string('/', slash));
                Console.Write(new string(':', 1));
                Console.Write(new string('X', x));
                Console.Write(new string(':', 1));
                x++;
                freeSpace--;
                Console.WriteLine();
            }

            Console.Write(new string(':', n - 1));
            Console.Write(new string(':', 1));
            Console.Write(new string('X', x));
            Console.Write(new string(':', 1));
            Console.WriteLine();

             freeSpace = n - 2;
             x--;
            for (int i = 0; i < n - 1; i++)
            {
                if (i + 1 == n - 1)
                {
                    Console.Write(new string(':', 1));
                    Console.Write(new string(':', freeSpace));
                    Console.Write(new string(':', 1));
                    Console.WriteLine();
                    break;
                }
                Console.Write(new string(':', 1));
                Console.Write(new string(' ', freeSpace));
                Console.Write(new string(':', 1));
                Console.Write(new string('X', x));
                Console.Write(new string(':', 1));

                x--;
                Console.WriteLine();
            }

        }
    }
}