SquareFrame

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

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

            for (int i = 0; i < n; i++)
            {
                if(i == 0 || i == n - 1)
                {
                    Console.WriteLine("+" + new string('-', n - 2) + "+");
                }
                else
                {
                    Console.WriteLine("|" + new string('-', n - 2) + "|");
                }
            }
        }
    }
}