using System;

namespace _00_ConsoleApp1
{
    class Program
    {

        static void Main()
        {
            // Get user input
            var n = int.Parse(Console.ReadLine());

            string row1 = new string('*', n);
            string row2 = new string(' ', n - 2);
            string square = row1 + Environment.NewLine;


            for(int i = 2; i < n; i++)
            {
                square += "*" + row2 + "*" + Environment.NewLine;
            }

            square += row1;

            Console.WriteLine(square);

        }
    }
}