import sys
import random
import string
import operator

def strxor(a, b): # xor two strings (trims the longer input)
  return "".join([chr(ord(x) ^ ord(y)) for (x, y) in zip(a, b)])

def hexxor(a, b): # xor two hex strings (trims the longer input)
  ha = a.decode('hex')
  hb = b.decode('hex')
  return "".join([chr(ord(x) ^ ord(y)).encode('hex') for (x, y) in zip(ha, hb)])

def main():

  #Plaintexts
  s1 = 'floare'
  s2 = 'albina'
  G = '' #To find

  #Obtain crc of s1
  #See this site:
  #http://www.lammertbies.nl/comm/info/crc-calculation.html
  x1 = s1.encode('hex')
  x2 = s2.encode('hex')
  print "x1: " + x1
  crc1 = '8E31' #CRC-16 of x1

  #Compute delta (xor) of x1 and x2:
  xd = hexxor(x1, x2)
  print "xd: " + xd


if __name__ == "__main__":
  main()