Квадратна рамка; Square Frame

using System;

namespace tESt
{
    class Program
    {
        static void Main(string[] args)
        {
            var n = double.Parse(Console.ReadLine());


            Console.Write("+ ");

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


            for (int i = 1; i < n - 1; i++)
            {
                Console.Write("| ");
                for (int j = 1; j <= n - 2; j++)
                {
                    Console.Write("- ");
                }
                Console.Write("| ");

                Console.WriteLine();
            }
            Console.Write("+ ");

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

            }
            Console.WriteLine("+ ");




        }
    }
}