procedure TForm1.Button1Click(Sender: TObject);
begin
 if (Edit1.Text<>'') and (Edit2.Text<>'') and (Edit3.Text<>'')and (Edit4.Text<>'') then
  begin
   Label9.Caption:='Спасибо за использование!';
   a:=StrToInt(Edit1.Text);
   b:=StrToInt(Edit2.Text);
   c:=StrToInt(Edit3.Text);
   d:=StrToInt(Edit4.Text);
   e:=1-d/100;
   f:=b/a*c*e;
   g:=b/a*c;
   Label6.Caption:=FloatToStr(f);
   Label8.Caption:=FloatToStr(g);
  end else ShowMessage('Все поля обязательны к заполнению');
end;

procedure TForm1.Edit1KeyDown(Sender: TObject; var Key: Word; Shift: TShiftState);
var i: integer; str:string;
begin
  if (((Key = ord('V')) and (ssCtrl in Shift)) or ((Shift = []) and (Key = VK_INSERT))) then
  begin
   if Clipboard.HasFormat(CF_TEXT) then
   begin
    str:=clipboard.AsText;
    ClipBoard.Clear;
    for i:=1 to length(str) do
    begin
     case str[i] of #48..#57: clipboard.AsText:=clipboard.AsText+str[i];
    end;
    key := 0;
   end;
  end;
end;

end;


procedure TForm1.Edit1KeyPress(Sender: TObject; var Key: Char);
begin
if not(key in ['0'..'9',#27,#8]) then key:=#0;
end;

 procedure TForm1.Memo1KeyDown(Sender: TObject; var Key: Word; Shift: TShiftState);   begin          ClipBoard.Clear;       end;