using System;

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

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

            if (n <= 2)
            {
                Console.WriteLine("**");
            }
            else
            {
                string asterisks = new string('*', n);
                string spaces = new string(' ', n - 2);
                Console.WriteLine(asterisks);

                for (int i = 1; i <= n - 2; i++)
                {
                    Console.Write("*");
                    Console.Write(spaces);
                    Console.WriteLine("*");
                }

                Console.WriteLine(asterisks);
            }
        }
    }
}