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Thread: help me please, I'm stuck.

  1. #1
    Junior Member
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    Mar 2014
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    Default help me please, I'm stuck.

    Programming Assignment
    Encryption Program
    In this program you are going to write a class that can be used for encoding and decoding messages. Your program will need two classes. The first class contains the main method and is used to test the second class. The second class contains two public methods. One called Encrypt which takes a string and returns an encrypted (coded) version of the string and one called Decrypt which takes an encrypted string and returns the decrypted (decoded) string.

    Please note that the decrypted message you return must result from the Decrypt method. You cannot just echo the message string.
    The Encryption Algorithm
    You should build your encrypted text using the following pseudocoded algorithm.
    For each character in the message
    Get the current character
    Convert the character into a two-character hexadecimal string
    Create a new character that consists of the concatenation of
    a random uppercase character + the first hex digit +
    a random uppercase character + the second hex digit
    Concatenate this new character to the encrypted text you are going to return
    Return the encrypted text.
    For example, if you send the message “hi” the hexadecimal code for the “h” is 68 and the hexadecimal code for “I” is 69. Your algorithm should return something like “R6X8T6R9” depending on the random characters generated by your method. Note the random characters interspersed between the 68 and the 69.
    The Decryption Algorithm
    You decryption algorithm needs to restore the original message by removing the random characters to
    recover the original hexadecimal code for the character. Remember that each character has been
    turned into a 4-character string. So you will have to extract the four encoded characters that make up
    each character in the original message as a unit. Also remember that the character you extracted is
    coded as a hexadecimal string. To recover the original character from the hexadecimal string you can
    use the following line of code
    c = (char) Integer.parseInt(character,16);
    Here’s a pseudocoded version of the decryption algorithm.
    For the length of the encrypted string
    Extract 4 characters
    Reconstruct the original hex string by removing the 2 random characters
    Create the character encoded by the hex string
    Concatenate the character to the decoded string you are going to return
    Return the decoded string
    Before you start this program be sure you have studied the string functions in chapter 4, the for-loop in
    chapter 5 and the examples we did in class.

  2. #2
    Join Date
    Oct 2013
    Manila, Philippines
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    Default Re: help me please, I'm stuck.

    help me please, I'm stuck.
    stuck with what?
    what have you tried?
    do you have codes? errors with your code?
    paste your code together with your question, we will try to help

  3. #3
    Super Moderator
    Join Date
    Jun 2013
    So. Maryland, USA
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    Default Re: help me please, I'm stuck.

    We don't give code, but we'll help you with yours. What have you tried? Post your code with any errors and then ask specific questions about what you need help with. "I'm stuck," just doesn't cut it.

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