Cryptography, or cryptology is the practice and study of techniques for secure communication. Cryptography relies on using more or less complex encryption algorithms to encode a readable message (plaintext) into a collection of characters (ciphertext) that is hard to decipher (decode).
For this challenge, we are giving you a piece of Python code used to encrypt a message.
Your first task is to reverse-engineer this code to understand how this encryption algorithm works. Then, your challenge consists of writing a new function called decrypt(), that takes two parameters (a ciphertext and a key) and returns the plaintext corresponding to the given ciphertext.
Decryption Table..
Using your new decrypt() function, decrypt the following messages:
# | Ciphertext | Key | Plaintext? |
#1 | YFwoJeELOvlDVrOlNBDConouLwhdCC mkIjsYeKsuaGsDbSRJymLJVOaYNQRrgKBSifPOdnCbUleWCbf | 4 | |
#2 | HNABntvVepMaQSNHyKxQTXZf HVbQXcqJSXfswOAuRBzpefOdfBeylimeqDHDlFc | 7 | |
#3 | PqKgakYBpfzveAHVrrUgbzpkaMWUcskukxac QfsWpFSrTrwiaQRtSsXesGlrBqv | 3 | |
#4 | HXelrEed fCxojmVersu Gtehvee NSluGnJ | 1 | |
#5 | PHcRrveeRUmDnfqMFAnBJvvwyzSDrj tqXhrLRXIegaDLwdInIGCvqelcjzU | 5 |
Solution...
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