Python Caesar cipher ascii adding spaces

user_8626448 0
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I'm trying to make the Caesar cipher and I'm having a problem with it.

It works perfectly but I want to have spaces added to the word that is inputted. If you enter a sentence with spaces in it. It just prints out = instead of a space when it is Encrypted. Can anyone help me fix this so that it will print out spaces?

Here is my code:

word = input("What is the message you want to encrypt or decrypt :")
def circularShift(text, shift):
    text = text.upper()
    cipher = "Cipher = "
    for letter in text:
        shifted = ord(letter) + shift
        if shifted < 65:
            shifted += 26
        if shifted > 90:
            shifted -= 26
        cipher += chr(shifted)
        if text == (" "):
            print(" ")
    return cipher
print (word)
print ("The encoded and decoded message is:")
print ("")
print ("Encoded message  = ")
print (circularShift(word , 3))
print ("Decoded message  = ")
print (circularShift(word , -3))
print ("")
input('Press ENTER to exit')
ascii python
2 Answers

You need to take a close look at your conditions:

Given a space, ord(letter) + shift will store a 32+shift in shifted (35 when shift is 3). That is < 65, therefore 26 gets added, in this case leading to 61, and the character with number 61 happens to be =.

To fix this, make sure to only touch characters that are in string.ascii_letters, for example as the first statement in your loop:

import string

...
for letter in text:
    if letter not in string.ascii_letters:
        cipher += letter
        continue
...
user_10162160

Just split the content:

print (word)
print ("The encoded and decoded message is:")
print ("")
print ("Encoded message  = ")
encoded = " ".join(map(lambda x: circularShift(x, 3), word.split()))
print (encoded)
print ("Decoded message  = ")
encoded = " ".join(map(lambda x: circularShift(x, -3), encoded.split()))
print (encoded)
print ("")

Here you have a live example

user_16951720
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