Wolfram Function Repository
Instantuse addon functions for the Wolfram Language
Function Repository Resource:
Decipher a Caesarenciphered string
ResourceFunction["CaesarDecipher"][string,n] deciphers a Caesarenciphered string that was enciphered by shifting letters in string by n places further in the Latin alphabet. 

ResourceFunction["CaesarDecipher"][{s_{1},s_{2},…},n] deciphers each string s_{i}. 

ResourceFunction["CaesarDecipher"][n] represents an operator form of ResourceFunction["CaesarDecipher"] that can be applied to an expression. 
Perform a Caesar decipher with a shift of 2:
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Decipher a text by shifting the letters 9 positions back:
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Cipher/decipher using a shift of n=13, also known at the ROT13 cipher:
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Decipher multiple strings:
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Create an operator form of the function that deciphers with a shift of 5:
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Use the operator:
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Decipher a message:
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Decipher a message:
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Enciphering can be done using the deciphering function but with a negative shift:
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If the shift is an integer multiple of 26, the Caesar decipher does not affect the input string:
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Try out all 25 options to decipher a message and find the original message:
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