using System;

public class Program

{

    public static void Main()

    {

        int[,] matrix = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 } };

        int sum = 0;

        for (int i = 0;

             i < matrix.GetLength(0); i++) {

            for (int j = 0; j < matrix.GetLength(1); j++) {

                sum += matrix[i,j];

            }

        }

        Console.WriteLine("Sum of all elements : " + sum);

    }

}