Learn String Manipulation by Building a Cipher - Step 75

Python
1

Tell us what’s happening:

Describe your issue in detail here.

Your code so far

text = 'Hello Zaira!'
custom_key = 'python'

def vigenere(message, key, direction=1):
    key_index = 0
    alphabet = 'abcdefghijklmnopqrstuvwxyz'
    final_message = ''

    for char in message.lower():

/* User Editable Region */

        # Append space to the message
        if char.isalpha() == ' ':
            final_message += char.isalpha()

/* User Editable Region */

        else:        
            # Find the right key character to encode/decode
            key_char = key[key_index % len(key)]
            key_index += 1

            # Define the offset and the encrypted/decrypted letter
            offset = alphabet.index(key_char)
            index = alphabet.find(char)
            new_index = (index + offset*direction) % len(alphabet)
            final_message += alphabet[new_index]
    
    return final_message
    
encryption = vigenere(text, custom_key)
print(encryption)
decryption = vigenere(encryption, custom_key, -1)
print(decryption)

Help here

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Challenge Information:

Learn String Manipulation by Building a Cipher - Step 75

2

You appear to have created this post without editing the template. Please edit your post to Tell us what’s happening in your own words.

3

Hello Waswabrian,

The .isalpha() method checks if a provided string or character contains only letters. So what you are doing now is trying to add True to final_message. Instead you just want to add char to the final_message

1 Like
4

I’m still not getting what you are saying

5

You don’t have to add isalpha() you only want to add char to final_message.

6

Still doesn’t work even if i remove it

7

adding to @HungryBee 's post

@Waswabrian only need if char.isalpha(): remove == ' ' from condition

1 Like
8

Can you share your latest code?

9

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