Square_Frame

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

namespace Square_Frame
{
    class Square_Frame
    {
        static void Main(string[] args)
        {
            int n = int.Parse(Console.ReadLine());
            if (n > 0)
            {
                Console.Write("+");
                for (int i = 1; i <= n - 2; i++)
                {
                    Console.Write(" -");
                }
                Console.WriteLine(" +");
                for (int j = 1; j <= n - 2; j++)
                {
                    Console.Write("| ");
                    for (int k = 1; k <= n - 2; k++)
                    {
                        Console.Write("- ");
                    }
                    Console.WriteLine("|");
                }
                Console.Write("+");
                for (int l = 1; l <= n - 2; l++)
                {
                    Console.Write(" -");
                }
                Console.WriteLine(" +");
            }
            else return;
        }
    }
}