Multiarray + foreach

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp16
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void btnKnap_Click(object sender, EventArgs e)
        {
            int[,] min2DimArray = new int[4, 3];

            min2DimArray[0, 0] = 20;
            min2DimArray[0, 1] = 22;
            min2DimArray[0, 2] = 21;

            min2DimArray[1, 0] = 50;
            min2DimArray[1, 1] = 49;
            min2DimArray[1, 2] = 52;

            int temp = 0;
            foreach (int mitelement in min2DimArray)
            {
                lstUd.Items.Add(mitelement.ToString());
                temp = temp + mitelement;
            }

            lstUd.Items.Add(temp.ToString());
        }
    }
}