3. Write a program to encrypt and decrypt strings of characters using the following ciphers:
a) Caesar cipher
b) Vigenere cipher
c) Matrix transposition cipher
Your program should contain functions/methods to encrypt a given plaintext string of characters and a key and generate the corresponding ciphertext. It should also contain functions/methods to decrypt a ciphertext string of characters and generate the corresponding plaintext. Submit the source codes and sample runs of the program.