Algorithm Sundays: Encrypting and Decrypting the Vigenère Cipher

We're back for another Algorithm Challenge. Today we will be looking at a cipher that was considered to be unbreakable for over three centuries. It was only in the middle of the 19th century, that the code breakers finally caught up with this ingenious method of encryption. The Vigenère Cipher originated at a time when cryptography was flourishing. Encrypting sensitive messages had not only become an important part of military and diplomatic communication but found its way into private households as well. Talented cryptanalysts were sought out across nations to decipher encrypted messages of enemies. More and more ciphers were broken by those cryptanalysts and in consequence, did not offer the security that was needed to ensure safe communication anymore.… read more »

Algorithm Sundays: Decrypting a ROT-13 Caesar Cipher

Is there anything better than starting your Sunday with a steaming hot mug of coffee and an algorithm challenge to get your brain juices flowing? I don't think so. Writing algorithms is a perfect way for you to stay sharp and be prepared for all kinds of challenges life (or your boss) is throwing at you. Please keep in mind that for most problems there are many ways to solve them and it's difficult to decide for a best solution. The one that runs quickest? The one that takes the least lines of code? The one that can be read easiest by your colleagues? I highly encourage you to take some time and think about the presented problem first. Try… read more »