Matrix - main sums

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

namespace Matrixx
{
    class Program
    {
        static void Main(string[] args)
        {
            Random rand = new Random();
            int n = int.Parse(Console.ReadLine());
            int[,] matrix = new int[n, n];

            for (int row = 0; row < matrix.GetLength(0); row++)
            {
                for (int col = 0; col < matrix.GetLength(1); col++)
                {
                    matrix[row, col] = rand.Next(0, 3);
                }
            }

            for (int row = 0; row < matrix.GetLength(0); row++)
            {
                for (int col = 0; col < matrix.GetLength(1); col++)
                {
                    Console.Write("{0:D2} ", matrix[row, col]);
                }
                Console.WriteLine();
            }

            int sum = 0;
            for (int row = 0; row < matrix.GetLength(0); row++)
            {
                for (int col = 0; col < matrix.GetLength(1); col++)
                {
                    if (col == row)
                    {
                        sum += matrix[row, col];
                    }
                }
            }
            Console.WriteLine("Primary diagonal sum = {0}", sum);

            sum = 0;
            for (int row = 0; row < matrix.GetLength(0); row++)
            {
                for (int col = 0; col < matrix.GetLength(1); col++)
                {
                    if ((col + row) == n - 1)
                    {
                        sum += matrix[row, col];
                    }
                }
            }
            Console.WriteLine("Secondary diagonal sum = {0}", sum);

        }
    }
}