So, this letter substitution cipher shows an error whenever there is a space (whitespace) in the input/phrase,to be encoded.
Here is my code: Im quite new to python so it would be helpful for any suggestions whatsoever.
from string import ascii_lowercase import random EXAMPLE_KEY = ''.join(sorted(ascii_lowercase, key=lambda _:random.random())) def encode(plaintext, key): return ''.join(key[ascii_lowercase.index(char)] for char in plaintext) def decode(plaintext, key): return ''.join(ascii_lowercase[key.index(char)] for char in plaintext) original = input("PLease enter a phrase: ") encoded = encode(original, EXAMPLE_KEY) decoded = decode(encoded, EXAMPLE_KEY) print("The original is:", original) print("Encoding it with the key:", EXAMPLE_KEY) print("Gives:", encoded) print("Decoding it by the same key gives:", decoded)
Note this isn’t a Caesar Cipher, simply randomly changing the letters to other letters. Thank you
ascii_lowercase does not contain a space, so
ascii_lowercase.index(char) is a ValueError.
One reasonable approach is to just catch this error and return the same character. That would require breaking your join call out into a loop. You could shoehorn an
if char in ascii_lowercase into there to keep it in one line, but that would be pretty ugly.
EDIT: like this
def encode(plaintext, key): ret = '' for char in plaintext: try: ret += key[ascii_lowercase.index(char)] except ValueError: ret += char return ret