Hill Cipher Encryption/Decryption

Hill Cipher belongs to a category of  Block Ciphers and Ployalphabetic ciphers.

• In a Hill Cipher , the key is a Square matrix of size m x m in which m is the size of block.

Encryption:

C.T = (P.T * Key   ) mod 26 

Decryption:

P.T = (C.T * Key^-1  ) mod 26

The Key matrix in the hill Cipher needs to have a multiplicative Inverse.

^Example:

^{Perform Encryption/Decryption on Given Plain Text "Attack is Tonight" .} 

P.T = (C.T * Key^-1  ) mod 26























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