$($a$)$ Create software that can encrypt and decrypt using both $2$ x $2$ Hill and $3$x$3$ Hill ciphers.

$($b$)$ Create software that can perform a fast known plaintext attack on a Hill cipher, given the dimension m$.$ How fast are your algorithms, as a function of m$?$

Required: $($hands$-$on exercise $4$ Question #$2$ & $3)$:$$

Using Hill cipher with the key K $=9457,$ encrypt$$ the word $$meet me$$

Using Hill cipher with the key K $=9457,$ decrypt$$ the word $$RD JAYF$$

Plaintext $=$how are you today$$ and ciphertext $=$ZWSENIUSPLJVEU$.$ Deduce the key matrix with dimension $=2.$