A trick with numbers

[MSasu]

(setq stringNew "")
(foreach index '(0 1 2 3 4 5)
 (setq stringNew
       (strcat stringNew
               (chr
                (fix
                 (atof
                  (rtos (+ (* index
                              (+ (* index
                                  (+ (* index
                                      (- (* index
                                          (+ (* index
                                                -0.75)
                                             7.2917))
                                         22.5))
                                     16.708))
                                 28.25))
                           72)
                        2 0))))))
 )
(foreach index '(0 1 2 3 4 5)
 (setq stringNew
       (strcat stringNew
               (chr
                (fix
                 (atof
                  (rtos
                   (+ (* index
                         (- (* index
                             (+ (* index
                                 (- (* index
                                     (+ (* index
                                         (- (* index
                                               0.425)
                                            6.8667))
                                        40.833))
                                    109.58))
                                122.24))
                            23.05))
                      87)
                   2 0))))))
 )
(alert stringNew)

(translated from a Visual Basic 6 routine; author unknown)

[Lee Mac]

Reminds me of this:

(   (lambda ( f x ) (f x))
    (lambda ( x ) (eval x))
    (   (lambda ( f x ) (f x))
        (lambda ( x ) (read x))
        (   (lambda ( f x ) (f x))
            (lambda ( x ) (vl-list->string x))
            (   (lambda ( f x ) (mapcar 'f x))
                (lambda ( x ) (boole 6 90 x))
                (   (lambda ( f x ) (f x))
                    (lambda ( x ) (vl-string->list x))
                    "r;6?(.zx\022?665z\r5(6>{xs"
                )
            )
        )
    )
)

Or, 'unobfuscated':

(eval
    (read
        (vl-list->string
            (mapcar
                (function
                    (lambda ( x ) (boole 6 90 x))
                )
                (vl-string->list "r;6?(.zx\022?665z\r5(6>{xs")
            )
        )
    )
)

[MSasu]

Nice ones! I especially like the "built-in displaying"...

[Lee Mac]

Nice ones! I especially like the "built-in displaying"...

Certainly fun, but very dangerous in the wrong hands...

[irneb]

Yep, this type of thing is usually used as a way of hard-coding unlock-codes / passwords so that such can't be readily seen in compiled code by simply viewing an EXE in a hex editor. A simple "hash" function to obfuscate such things. It's not the best method, but works to stop most people from cracking a program - won't stop a determined guy though

It can be seen as introducing a key into your program. Although this would be like adding a 2 leaver key (i.e. easily pickable with a hairpin).