unit Unit1;

{$mode objfpc}{$H+}

interface

uses

  Classes, SysUtils, FileUtil, Forms, Controls, Graphics, Dialogs, StdCtrls,

  ExtCtrls;

type

  { TForm1 }

  TForm1 = class(TForm)

    Edit1: TEdit;

    Edit2: TEdit;

    Timer1: TTimer;

    procedure Timer1Timer(Sender: TObject);

  private

    { private declarations }

  public

    { public declarations }

  end;

var

  Form1: TForm1;

implementation

{$R *.lfm}

{ TForm1 }

procedure TForm1.Timer1Timer(Sender: TObject);

var

  i, j: integer;

  text1, text2, chars: string;

begin

  text1 := Edit1.Text;

  text2 := Edit2.Text;

  chars := 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ' + text1;

  for i := 1 to length(text1) do begin

    if length(text2) < i then text2 := text2 + '*';

    for j := 0 to 0 do

      if text1[i] <> text2[i] then text2[i] := chars[Random(length(chars)+1)];

  end;

  Edit2.Text := copy(text2, 1, length(text1));

end;

end.