Question

How can i apply the xor of two binary strings that represents the bin of two characters ?

here is a code

def Xor(a,b):

    ABytes = a.encode('ascii','strict')
    BBytes = b.encode('ascii','strict')

    ABinaries = bin(int(binascii.hexlify(ABytes),16))
    BBinaries = bin(int(binascii.hexlify(BBytes),16))

    #this is what i want to do:
    xor = ABinaries ^ BBinaries 

    return xor

But since the ^ operator does not operate on strings. the code does not work, the problem is that i need to return the binary value of the xor.

And if it worked, how can i get the string value of the xor ?

Answer 1

When you index or iterate bytes in Python 3, you get int values that you can xor:

>>> a, b = b'abc', b'def'
>>> c = bytes(x^y for x,y in zip(a, b))
>>> c
b'\x05\x07\x05'
>>> bytes(x^y for x,y in zip(a, c))
b'def'
>>> bytes(x^y for x,y in zip(b, c))
b'abc'

If I wanted this as a bit string for some reason (representation? I certainly wouldn’t calculate with it), I’d use the built-in format, and zero pad each bitstring to 8 bits:

>>> ''.join(format(x, '08b') for x in c)
'000001010000011100000101'