Results 1 to 2 of 2
Like Tree1Likes
  • 1 Post By pbrockway2

Thread: How do you get the inverse of this transformation?

  1. #1
    EscSequenceAlpha is offline Senior Member
    Join Date
    Apr 2012
    Posts
    115
    Rep Power
    0

    Default How do you get the inverse of this transformation?

    Ok so I'm doing a programming exercise which gives me a method of encryption, one of the steps is to +7 then mod 10

    besides from the encryption application itself I must also decrypt... but surely this is impossible.

    mod provides a many-to-one relationship for example (3 mod 10 = 3) and (13 mod 10 = 3) so information is lost making it impossible to decrypt (atleast thats what my common sense says)

    unless I've missed something, maybe I must get additional information from the user but then what would that be and how would it be applied?

    how can you reverse that kind of transformation in the simplest way?

    thanks

  2. #2
    pbrockway2 is offline Moderator
    Join Date
    Feb 2009
    Location
    New Zealand
    Posts
    4,585
    Rep Power
    12

    Default Re: How do you get the inverse of this transformation?

    Yes, your common sense is correct. The step can only possibly be reversed if there were 10 or fewer symbols being encrypted.

    But if that step occurred as *part* of an encryption process it is quite possible that the process as a whole can be reversed.
    EscSequenceAlpha likes this.

Similar Threads

  1. Modular Inverse Function issues.
    By christopherx in forum Advanced Java
    Replies: 0
    Last Post: 10-28-2011, 09:36 PM
  2. Matrix Inverse
    By TryingMybestInJava in forum New To Java
    Replies: 4
    Last Post: 12-01-2010, 12:59 AM
  3. Inverse Cos
    By dilpreet28 in forum Java Applets
    Replies: 2
    Last Post: 06-11-2010, 01:23 AM
  4. Transformation
    By rosh72851 in forum New To Java
    Replies: 1
    Last Post: 11-19-2008, 05:11 PM
  5. inverse engineering
    By Ed in forum JDBC
    Replies: 2
    Last Post: 07-02-2007, 08:57 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •