Не знаю как делать,подскажите

while length(s)<=m*n do//m,n-размер таблицы
s:=s+'0';

unit Unit1;
 
interface
 
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Grids;
 
type
  TForm1 = class(TForm)
    Label1: TLabel;
    stringgrid1: TStringGrid;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    Edit2: TEdit;
    Edit1: TEdit;
    Label2: TLabel;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
 
var
  Form1: TForm1;
 
implementation
 
{$R *.dfm}
 
procedure TForm1.Button1Click(Sender: TObject);
var txt,buf:string;
 dlina,stroka,stolb:integer;
 i,l:integer;
begin
stolb:=0;
stroka:=0;
l:=0;
txt:=edit1.Text;
dlina:=length(txt);
 
 
for i:=1 to dlina do begin
 buf:=txt[i];
 if l=stringgrid1.RowCount then begin
  stolb:=stolb+1;
  stroka:=0;
  l:=0;
   end;
 stringgrid1.Cells[stolb,stroka]:=buf;
 
 stroka:=stroka+1;
 l:=l+1;
  end;
edit1.Text:='';
 end;
 
procedure TForm1.Button2Click(Sender: TObject);
var txt:string;
 i,j:integer;
 stolb,stroka,l:integer;
begin
txt:='';
stolb:=0;
stroka:=0;
l:=0;
for i:=0 to stringgrid1.ColCount*stringgrid1.RowCount do begin
 if l=stringgrid1.ColCount then begin
  stolb:=0;
  stroka:=stroka+1;
  l:=0;
   end;
 txt:=txt+stringgrid1.Cells[stolb,stroka];
 stolb:=stolb+1;
 l:=l+1
  end;
edit2.Text:=txt;
 
 
stroka:=0;
stolb:=0;
for i:=0 to stringgrid1.ColCount do begin
 for j:=0 to stringgrid1.RowCount do begin
 stringgrid1.Cells[i,j]:='';
  end;
 end;
end;
procedure TForm1.Button3Click(Sender: TObject);
var txt,buf:string;
 stroka,stolb,l:integer;
 i,j,dlina:integer;
begin
txt:=edit2.Text;
dlina:=length(txt);
stroka:=0;
stolb:=0;
l:=0;
for i:=1 to dlina do begin
 buf:=txt[i];
 if l=stringgrid1.ColCount then begin
  stroka:=stroka+1;
  stolb:=0;
  l:=0;
   end;
 stringgrid1.Cells[stolb,stroka]:=buf;
 stolb:=stolb+1;
 l:=l+1;
  end;
edit2.Text:='';
stolb:=0;
stroka:=0;
l:=0;
txt:='';
for i:=0 to stringgrid1.ColCount*stringgrid1.RowCount do begin
 if l=stringgrid1.RowCount then begin
  stolb:=stolb+1;
  stroka:=0;
  l:=0;
   end;
 txt:=txt+stringgrid1.Cells[stolb,stroka];
 stroka:=stroka+1;
 l:=l+1;
  end;
edit1.Text:=txt;
label1.Caption:='';
stroka:=0;
stolb:=0;
for i:=0 to stringgrid1.ColCount do begin
 for j:=0 to stringgrid1.RowCount do begin
 stringgrid1.Cells[i,j]:=''
  end;
 end;
end;
end.