decoding an ASCII character message

Question

I have no idea what im doing I need to decode mmZ\dxZmx]Zpgy, I have an example but not sure what to do please help!

 If (EncryptedChar - Key < 32) then

 DecryptedChar = ((EncryptedChar - Key) + 127) - 32

Else

DecryptedChar = (EncryptedChar - Key)

the key us unknown 1-100

Answer 1

Use ord and chr to convert between the ordinals (ord) of the ASCII value and the and the characters (chr) they represent.

Then you can loop through your string and apply the your algorithm to each.

For example:

import sys
SecretMessage = "mmZ\dxZmx]Zpgy"
Key = 88
for Letter in SecretMessage:
    EncryptedChar = ord(Letter)
    if (EncryptedChar - Key) < 32:
        DecryptedChar = ((EncryptedChar - Key) + 127) - 32
    else:
        DecryptedChar = (EncryptedChar - Key)
    sys.stdout.write(chr(DecryptedChar))

Run this to see the output. I'll leave the exercise of finding the key value 88 up to you (hint: it involves iterations). You also appear to be missing the first letter from SecretMessage (probably a :).