-----cut-----
 
procedure TForm1.Edit1Change(Sender: TObject);
begin
  if Edit1.Text <> '' then
  StringGrid1.ColCount := StrToInt(Edit1.Text);
end;
 
procedure TForm1.Edit2Change(Sender: TObject);
begin
  if Edit2.Text <> '' then
  StringGrid1.RowCount := StrToInt(Edit2.Text);
end;
 
procedure TForm1.FormCreate(Sender: TObject);
begin
  Edit1.Text := '5';
  Edit2.Text := '5';
  StringGrid1.FixedCols := 0;
  StringGrid1.FixedRows := 0;
  StringGrid1.ColCount := 5;
  StringGrid1.RowCount := 5;
  StringGrid1.Options := StringGrid1.Options + [goEditing];
end;
 
procedure TForm1.Button1Click(Sender: TObject);
var
  i,j: Integer;
  S: Integer; // Переменная для подсчета суммы
begin
  S := 0;
  for i := 0 to StringGrid1.ColCount - 1 do
    for j := 0 to StringGrid1.RowCount - 1 do begin
      if StringGrid1.Cells[i,j] = '' then Exit;
      if StrToInt(StringGrid1.Cells[i,j]) > 0 then S := S + StrToInt(StringGrid1.Cells[i,j]);
    end;
  Edit3.Text := IntToStr(S);
end;
 
-----cut-----