Как перемножить две матрицы, которые пользователь вписывает в stringgrid?

unit Unit1;
 
interface
 
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, Grids, StdCtrls;
 
type
  TForm1 = class(TForm)
    Label1: TLabel;
    Edit1: TEdit;
    StringGrid1: TStringGrid;
    Button1: TButton;
    StringGrid2: TStringGrid;
    Button2: TButton;
    Edit2: TEdit;
    Label2: TLabel;
    StringGrid3: TStringGrid;
    Label3: TLabel;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
 
var
  Form1: TForm1;
  a, b:Integer;
  i, j:Integer;
 
 
implementation
 
{$R *.dfm}
 
procedure TForm1.Button1Click(Sender: TObject);
begin
a:=StrToInt(Edit1.Text);
b:=StrToInt(Edit2.Text);
StringGrid1.ColCount:=a+1;
StringGrid1.RowCount:=b+1;
StringGrid1.Cells[0,0]:='Массив 1';
StringGrid2.ColCount:=a+1;
StringGrid2.RowCount:=b+1;
StringGrid2.Cells[0,0]:='Массив 2';
Button1.Visible:=False;
StringGrid1.Visible:=True;
StringGrid2.Visible:=True;
Button2.Visible:=True;
Edit2.Visible:=False;
Edit1.Visible:=False;
Label1.Visible:=False;
Label2.Visible:=True;
end;
 
procedure TForm1.Button2Click(Sender: TObject);
begin
StringGrid1.Visible:=False;
StringGrid2.Visible:=False;
Label2.Visible:=False;
Label3.Visible:=True;
StringGrid3.ColCount:=a+1;
StringGrid3.RowCount:=b+1;
StringGrid3.Visible:=True;
end;
 
end.