CPSC120
Fundamentals of Computer Science

In-class Activity 18

1. Create a function called vigenere_encipher(text, key) that returns a string that enciphers the specified text using the specified key according to the Vigenère algorithm.

2. Create a function called vigenere_decipher(text, key) that returns a string that deciphers the specified text using the specified key according to the Vigenère algorithm.

3. Create a function called substitution_encipher(text, key) that returns a string that enciphers the specified text using the specified key according to the substitution algorithm.