AceOfDiamonds

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


class AceOfDiamonds
{
    static void Main()
    {
        int size = int.Parse(Console.ReadLine());

        int topDash = ((size - 1) / 2) - 1;
        int topSymbol = 1;

        int bottomDash = 1;
        int bottomSymbol = size - 4;

        string firstAndLastRow = new string('*', size); // First row

        Console.WriteLine(firstAndLastRow);

        while (topDash >= 0)
        {
            string insideUpRows = "*" + new string('-', topDash) + new string('@', topSymbol) + new string('-', topDash) + "*"; // Top half + middle part
            Console.WriteLine(insideUpRows);
            topDash--;
            topSymbol += 2;
        }

        while (bottomSymbol >= 1)
        {
            string insideDownRows = "*" + new string('-', bottomDash) + new string('@', bottomSymbol) + new string('-', bottomDash) + "*"; // Bottom half
            Console.WriteLine(insideDownRows);
            bottomDash++;
            bottomSymbol -= 2;
        }

        Console.WriteLine(firstAndLastRow); // Last row
    }
}