diamond shape in c#

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

namespace star_dimand
{
    class Program
    {
        static void Main(string[] args)
        {
            int i, j,n;
            Console.WriteLine("Enter no for printing star in diamond shape");
            n = int.Parse(Console.ReadLine());
            for (i = 1; i <= n; i++)
            {
                for (j = n; j >= i; j--)
                {
                    Console.Write(" ");
                }
                for (j = 1; j <= i; j++)
                {
                    Console.Write("*");
                }
                for (j = 1; j <= i; j++)
                {
                    Console.Write("*");
                }
                Console.WriteLine();
            }
            
          
            for (i = 1; i <= n; i++)
            {
                for (j = 0; j <=i; j++)
                {
                    Console.Write(" ");
                }
                for (j = n; j >= i; j--)
                {
                    Console.Write("*");
                }
                for (j = n; j >= i; j--)
                {
                    Console.Write("*");
                }
                Console.WriteLine();
            }
            Console.ReadKey();
        }
    }
}
output

Enter no for printing star in diamond shape
6
      **
     ****
    ******
   ********
  **********
 ************
  ************
   **********
    ********
     ******
      ****
       **