unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Menus;

type
  TForm1 = class(TForm)
    Edit1: TEdit;
    Edit2: TEdit;
    Edit3: TEdit;
    Button2: TButton;
    Button3: TButton;
    Button4: TButton;
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    Button1: TButton;
    MainMenu1: TMainMenu;
    N1: TMenuItem;
    N2: TMenuItem;
    N3: TMenuItem;
    N4: TMenuItem;
    procedure Button3Click(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button4Click(Sender: TObject);
    procedure N1Click(Sender: TObject);
    procedure N2Click(Sender: TObject);
    procedure N3Click(Sender: TObject);
    procedure N4Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  a,b,c:real;
implementation

uses Unit2, Unit3, Unit4, Unit5;

{$R *.dfm}

procedure TForm1.Button3Click(Sender: TObject);
begin
a:=strtofloat(Edit1.text);
b:=strtofloat(Edit2.text);
c:=a*b;
edit3.Text:=floattostr(c);
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
a:=strtofloat(Edit1.text);
b:=strtofloat(Edit2.text);
c:=a+b;
edit3.Text:=floattostr(c);
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
a:=strtofloat(Edit1.text);
b:=strtofloat(Edit2.text);
c:=a-b;
edit3.Text:=floattostr(c);
end;

procedure TForm1.Button4Click(Sender: TObject);
begin
a:=strtofloat(Edit1.text);
b:=strtofloat(Edit2.text);
c:=a/b;
edit3.Text:=floattostr(c);
end;

procedure TForm1.N1Click(Sender: TObject);
begin
form2.showmodal;
end;

procedure TForm1.N2Click(Sender: TObject);
begin
form3.showmodal;
end;

procedure TForm1.N3Click(Sender: TObject);
begin
form4.showmodal;
end;

procedure TForm1.N4Click(Sender: TObject);
begin
close;
end;

end.