Type: Substitution
> playfair cipher uses an array of 5x5 containing a keyword or phrase. The first step is to create a grid based on the key. The second step is to encrypt the letters of the message by selecting them in pairs.
Key: melons
(Note: grid size is 5x5 and i/j can interchange)
M|E|L|O|N
S|A|B|C|D
F|G|H|I |K
P|Q|R|T |U
V|W|X|Y|Z
Plaintext: VALENTINES VA LE NT IN ES
Ciphertext: WSOLOUJOMA WS OL OU JO MA
