Hello I'm having some trouble with my python code in making a Caesar's cipher. First, I'm only supposed to use one global constant , ALPHABET, but I don't think I can import string. So should I just include every alphabet letter in a bracket ( for ex: [A, B, C....].lower() ) or is there another method?In lines 18 and 19, I have i = ALPHABET.index(char) and encodeMessage += cipher[i] but should I replace the variable i with another variable name, since in line 17, I don't have it listed as , for char in message(i)?Instructions:The main() function will prompt the user for two values: a text message string consisting of only alphabetic characters and spaces, and a key value between 1 and 26.You will have one global constant list called ALPHABET, which will have lowercase letters and the space (in the order shown above) as elementsIn addition to main, your program will have 3 functions:The generateCipher() function will accept the parameter key and will generate and return the cipher alphabet list. Hint: create the cipher list by slicing the plaintext alphabet list (using the key), and return it.The encodeMessage () function will accept as parameters a string containing the plaintext message and the cipher alphabet list, and will return a string with the encoded messageThe decodeMessage () function will accept as parameters a string containing an encoded message and the cipher alphabet list, and will return a string with the plaintext message. If the original message contained uppercase letters, those will NOT be restored (they will be shown in lowercase).You may not use any global variables other than the constant(s) mentioned above Your program will take as input a plaintext message string consisting only of letters and spaces, and a numeric key value between 1 and 26. The program will display these input values, encode and output the ciphered message, and decode the encoded message back to plain text. A sample execution is shown below:```Enter the message you want to encode: my secretEnter the key: 6Encoding message 'my secret' with key 6Encoded: gsuzxlznDecoded: my secret``` ```python# The purpose of the program is to depict messages using a Caesar's cipherimport stringALPHABET = string.ascii_lowercasedef generateCipher(key_value): cipher = ALPHABET[-key_value:] + ALPHABET[:-key_value] return cipherdef encodeMessage(message, cipher): encodeMessage = "" for char in message: i = ALPHABET.index(char) encodeMessage += cipher[i] return encodeMessagedef decodeMessage(encodeMessage, cipher): decodeMessage = "" for char in encodeMessage: i = cipher.index(char) decodeMessage += ALPHABET[i] return decodeMessagedef main(): message = input("Enter the message you want to encode: ").lower() key_value = int(input("Enter the key: ")) if key_value < 1 or key_value > 26: key_value = int(input("Invalid key value. Try again: ")) cipher = generateCipher(key_value) encodeMessage = encodeMessage(message, cipher) print("Encoded: " + encode) decodeMessage = decodeMessage(encodeMessage, cipher) print("Decoded: " + decode)main()```### ExplanationThis Python script is designed to encode and decode messages using a Caesar cipher. The Caesar cipher is a type of substitution cipher where each letter in the plaintext is shifted a certain number of places down the alphabet.**Functions:**1. **`generateCipher(key_value)`:** - Generates a cipher alphabet by shifting the original alphabet by the `key_value`. - `key_value` determines how many positions each letter in the alphabet is shifted.2. **`encodeMessage(message, cipher)`:** - Encodes a message using the generated cipher. - Converts each character in the message into its corresponding character in the cipher.3. **`decodeMessage(encodeMessage, cipher)`:** - Decodes an encoded message back into plaintext. - Converts each character in the encoded message to the original alphabet character using the cipher.4. **`main()`:** - Takes input from the user for the message and the key value. - Checks the validity of the key (should be between 1 and 26). - Generates the cipher and encodes the message. - Prints the encoded and decoded message.The script uses Python's `string` library to

Python:- Advantages:- 1. Simple Syntax 2. Easy-to-use Data Structure 3. Learning Ease and Support Available 4. Nearness of Third-Party Modules 5. Broad Support Libraries 6. Open Source and Community DevelopmentAnswer:- Code:- 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', ' '] def generate_cipher(key): cipher = ALPHABET[-key:] + ALPHABET[:-key] return cipher def encode_message(message, cipher): encoded_message = ""; for ch in message: # index() method return the index of a given list element ind = ALPHABET.index(ch) encoded_message += cipher[ind] return encoded_message def decode_message(encoded_message, cipher): decoded_message = ""; for ch in encoded_message: ind = cipher.index(ch) decoded_message += ALPHABET[ind] return decoded_message if __name__ == '__main__': message = input('Enter the message to encode: ').lower() key = int(input('Enter the key: ')) while key < 1 or key > 26: key = int(input('Key must be between 1 and 26. Enter again: ')) cipher = generate_cipher(key) encoded = encode_message(message, cipher) print('Encoded Message: ' + encoded) decoded = decode_message(encoded, cipher) print('Decoded Message: ' + decoded)Screenshot:-Output:-

Answered: Hello I'm having some trouble with my…

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

See similar textbooks

Related questions

Concept explainers

Question

Hello I'm having some trouble with my python code in making a Caesar's cipher. First, I'm only supposed to use one global constant , ALPHABET, but I don't think I can import string. So should I just include every alphabet letter in a bracket ( for ex: [A, B, C....].lower() ) or is there another method?

In lines 18 and 19, I have i = ALPHABET.index(char) and encodeMessage += cipher[i] but should I replace the variable i with another variable name, since in line 17, I don't have it listed as , for char in message(i)?

Instructions:

The main() function will prompt the user for two values: a text message string consisting of only alphabetic characters and spaces, and a key value between 1 and 26.
You will have one global constant list called ALPHABET, which will have lowercase letters and the space (in the order shown above) as elements
In addition to main, your program will have 3 functions:
- The generateCipher() function will accept the parameter key and will generate and return the cipher alphabet list. Hint: create the cipher list by slicing the plaintext alphabet list (using the key), and return it.
- The encodeMessage () function will accept as parameters a string containing the plaintext message and the cipher alphabet list, and will return a string with the encoded message
- The decodeMessage () function will accept as parameters a string containing an encoded message and the cipher alphabet list, and will return a string with the plaintext message. If the original message contained uppercase letters, those will NOT be restored (they will be shown in lowercase).
You may not use any global variables other than the constant(s) mentioned above

Your program will take as input a plaintext message string consisting only of letters and spaces, and a numeric key value between 1 and 26. The program will display these input values, encode and output the ciphered message, and decode the encoded message back to plain text. A sample execution is shown below:

```
Enter the message you want to encode: my secret
Enter the key: 6
Encoding message 'my secret' with key 6
Encoded: gsuzxlzn
Decoded: my secret
```

```python
# The purpose of the program is to depict messages using a Caesar's cipher

import string

ALPHABET = string.ascii_lowercase

def generateCipher(key_value):
cipher = ALPHABET[-key_value:] + ALPHABET[:-key_value]
return cipher

def encodeMessage(message, cipher):
encodeMessage = ""
for char in message:
i = ALPHABET.index(char)
encodeMessage += cipher[i]
return encodeMessage

def decodeMessage(encodeMessage, cipher):
decodeMessage = ""
for char in encodeMessage:
i = cipher.index(char)
decodeMessage += ALPHABET[i]
return decodeMessage

def main():
message = input("Enter the message you want to encode: ").lower()
key_value = int(input("Enter the key: "))
if key_value < 1 or key_value > 26:
key_value = int(input("Invalid key value. Try again: "))
cipher = generateCipher(key_value)
encodeMessage = encodeMessage(message, cipher)
print("Encoded: " + encode)
decodeMessage = decodeMessage(encodeMessage, cipher)
print("Decoded: " + decode)

main()
```

### Explanation

This Python script is designed to encode and decode messages using a Caesar cipher. The Caesar cipher is a type of substitution cipher where each letter in the plaintext is shifted a certain number of places down the alphabet.

**Functions:**

1. **`generateCipher(key_value)`:**
- Generates a cipher alphabet by shifting the original alphabet by the `key_value`.
- `key_value` determines how many positions each letter in the alphabet is shifted.

2. **`encodeMessage(message, cipher)`:**
- Encodes a message using the generated cipher.
- Converts each character in the message into its corresponding character in the cipher.

3. **`decodeMessage(encodeMessage, cipher)`:**
- Decodes an encoded message back into plaintext.
- Converts each character in the encoded message to the original alphabet character using the cipher.

4. **`main()`:**
- Takes input from the user for the message and the key value.
- Checks the validity of the key (should be between 1 and 26).
- Generates the cipher and encodes the message.
- Prints the encoded and decoded message.

The script uses Python's `string` library to

Expert Solution

Trending now

This is a popular solution!

Step by step

Solved in 5 steps with 3 images

SEE SOLUTION Check out a sample Q&A here

Knowledge Booster

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, computer-science and related others by exploring similar questions and additional content below.