Sorted List

using System;
using System.Text.RegularExpressions;
using System.IO;
using Mono.CSharp;
using Android.Widget;
using Android.Content;
using Android.Views.InputMethods;
using System.Threading.Tasks;
using NativeUiLib; //This ads the GUI contols. Minor abstractions over Xamarin.Android/Mono.Android
namespace SORTED
{
    public static class Program
    {
        public static async void Main()
        {
            var Bolas = "01234567890987654321012345678901234567890123456789";
            string lista = null;
            int[] sf = new int[10];
            int z=0;
            var sort = new char[5]; var bola = new Random();
            var lay1 = new LinearLayout();
            //lay1.Orientation = Android.Widget.Orientation.Vertical;

            var lbl = lay1.AddTextView();
            var valor = lay1.AddEditText(true);


            //var lay2 = new LinearLayout();
            //lay2.Orientation = Android.Widget.Orientation.Horizontal;
            int N = 50000;
            var btn = lay1.AddButton();
            var btn1 = lay1.AddButton();
            var lbl1 = lay1.AddTextView();

            lbl1.SetPadding(4,5,5,0);
            if (valor.Text != "")
            {
                N = Convert.ToInt32(valor.Text);
            }
            string[] sorteo = new string[N];
            lbl.Text = " Xamarin.Forms/Mono.Android/App ";
            btn.Text = " SORTEAR ";
            btn1.Text = " BORRAR ";
            lay1.Show(); Console.Clear();
            //lay2.Show();
            await Task.Delay(300);
            btn.Click += delegate
            {
                if (valor.Text != "")
                {
                    N = Convert.ToInt32(valor.Text);
                }
                lista = null;
                for(int j=0; j<N; j++)
                {
                    for (int i=0; i < sort.Length; i++)
                    {
                        sort[i] = Bolas[bola.Next(Bolas.Length)];
                    }
                    sorteo [j] = new String(sort);
                }
                for(int k=0; k<N; k++)
                {
                    lista = lista + sorteo[k] + "  ";
                }
                for (int i=0; i<10; i++)
                {
                    sf[i]=0; z=0;
                    for(int j=0; j<N; j++)
                    {
                        string x = Convert.ToString(sorteo[j][4]);
                        if (x == $"{i}")
                        {
                            z++;
                        }
                    }
                    sf[i]=z;
                }
                lbl1.Text = $"Terminaciones de 0, 1, 2, 3, 4, 5, 6, 7, 8 y 9 respectivamente:\n {sf[0]},{sf[1]},{sf[2]},{sf[3]},{sf[4]},{sf[5]},{sf[6]},{sf[7]},{sf[8]},{sf[9]}\n\n" + lista;
            };
            btn1.Click += delegate
            {
                lbl1.Text = "";
                valor.Text = "";
                N=0;
                for (int i=0; i<10; i++)
                {
                    sf[i]=0;
                }
            };
        }
    }
}