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unit Unit3;
 
interface
 
uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls;
 
type
  TForm3 = class(TForm)
    Button1: TButton;
    Edit1: TEdit;
    Edit2: TEdit;
    Label1: TLabel;
    procedure Button1Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
  private { Private declarations }
    Step: integer;
    Text: String;
  public
    { Public declarations }
  end;
 
var
  Form3: TForm3;
 
implementation
 
{$R *.dfm}
 
function Shift(aText: String): String;
const Alph: String = 'АБВГДЕЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯ';
var i, k: integer;
begin
  result := '';
  for i := 1 to Length(aText) do
    begin
      k := Pos(aText[i], Alph) - 1;
      if k = 0 then result := result + Alph[Length(Alph)] else result := result + Alph[k];
    end;
end;
 
procedure TForm3.Button1Click(Sender: TObject);
begin
  if Step = 33 then Exit;
  Label1.Caption := 'Сдвиг на ' + IntToStr(Step);
  if Step = 1 then Text := Edit1.Text;
  Text := Shift(Text);
  Edit2.Text := Text;
  inc(Step);
end;
 
procedure TForm3.FormCreate(Sender: TObject);
begin
  Step := 1;
  Text := Edit1.Text;
end;
 
end.