SquareOfStars

using System;

    class SquareofStars
    {
        static void Main()
        {
            var n = int.Parse(Console.ReadLine());
            Console.WriteLine(new string('*', n));
            for (int i = 0; i < n - 2; i++)
            {
                Console.WriteLine('*' + new string(' ', n - 2) + '*');
            }
            Console.WriteLine(new string('*', n));
        }
    }