Задачи на двумерные массивы

unit Unit1;
interface
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Grids;
type
  TForm1 = class(TForm)
    StringGrid1: TStringGrid;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
const n=4;
var
  Form1: TForm1;
   a:array[0..n] of integer;
implementation
{$R *.dfm}
procedure TForm1.Button1Click(Sender: TObject);
var i,j:byte;
begin
randomize;
 for i:=0 to n do
 begin
 a[i]:=random(100);
 StringGrid1.Cells[i,0]:=IntToStr(a[i]);
 end;
end;
procedure TForm1.Button2Click(Sender: TObject);
var x:integer; i,j,k:byte;
begin
for i:=1 to n do
 begin
  x:=a[i];
  j:=0;
  while x>a[j] do j:=j+1;
  for k:=i-1 downto j do a[k+1]:= a[k];
  a[j]:=x;
 end;
for i:=0 to n do
StringGrid1.Cells[i,1]:=IntToStr(a[i]);
end;