Square Frame

using System;

class SquareFrame
{
    static void Main()
    {

        int n = int.Parse(Console.ReadLine());

        Console.Write('+');
        Console.Write(new string('-', n - 2));
        Console.WriteLine('+');
        for (int i = 0; i < n - 2; i++)
        {
            Console.Write('|');
            Console.Write(new string('-', n - 2));
            Console.WriteLine('|');

        }
        Console.Write('+');
        Console.Write(new string('-', n - 2));
        Console.WriteLine('+');
    }
}