encoding and decoding in python
alphabet = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z']
def caesar(start_text, shift_amount, cipher_direction):
end_text = ""
if cipher_direction == "decode":
shift_amount *= -1
for char in start_text:
if char in alphabet:
position = alphabet.index(char)
new_position = position + shift_amount
end_text += alphabet[new_position]
else:
end_text += char
print(f"Here's the {cipher_direction}d result: {end_text}")
should_end = False
while not should_end:
direction = input("Type 'encode' to encrypt, type 'decode' to decrypt:\n")
text = input("Type your message:\n").lower()
shift = int(input("Type the shift number:\n"))
shift = shift % 26
caesar(start_text=text, shift_amount=shift, cipher_direction=direction)
restart = input("Type 'yes' if you want to go again. Otherwise type 'no'.\n")
if restart == "no":
should_end = True
print("Thanks for using me")