Refactored, standarised

README.md

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+A Python implementation of the Playfair cipher
+
+The Playfair cipher was created by Charles Wheatstone and popularised by Lord Playfair (hence the name).
+Playfair is a classic (means not electronic) symmetric cipher (the same key is used for encryption and decryption)
+Using a password like "MONARCHY" we get a 5x5 matrix by using at first the distinct letters in our password
+and then the rest of the alphabet.
+
+|  | 1 | 2 | 3 | 4 | 5 |
+|---|---|---|---|---|---|
+|1|M|O|N|A|R|
+|2|C|H|Y|B|D|
+|3|E|F|G|I|K|
+|4|L|P|Q|S|T|
+|5|U|V|W|X|Z|
+
+Usually I and J are considered the same letter.
+After we split the text in digraphs, if a digraph is the same letter twice, then a double_padding letter is appended.
+If the plaintext has an odd number of letters, then an end_padding letter is appended.
+
+If the 2 letters are in the same row, each one is encrypted to the one to its right.
+If the 2 letters are in the same collumn, each one is encrypted to the one beneth it.
+Else, each letter is encrypted to the letter in the same row, but in the other's collumn
+
+Thus:
+EE becomes EX.. and is encpypted to IU..
+
+HD is encrypted to YC
+
+GW is encrypted to QN
+
+This is a rudimentary implementation of the Playfair cipher in python.
+Though not much, it gets the job done, it is beautiful, and scores 9.79/10 in pylint
+
+Modified a warm july evening the day before my graph theory exam.