HEX编码

import re
def encrypt_hex(string):
  ciphertext = ""
  lis = []
  for i in string:
    if ord(i) > 127:
      return -1
    lis.extend(re.findall("\d{4}",("0"*8+bin(ord(i))[2::])[-8::]))
  for i in lis:
    ciphertext += hex(int(i,2))[2::]
  return ciphertext
def decrypt_hex(string):
  plaintext = ""
  # 个数一定是2的倍数
  if len(string) % 2 != 0:
    return -1
  lis = re.findall(".{2}", string)
  for i in lis:
    # 判断字符是0-f
    if ord(i[0]) < ord("0") or ord(i[0]) > ord("f") or ord(i[1]) < ord("0") or ord(i[1]) > ord("f"):
      return -1
    plaintext += chr(int(i[0],16)*16+int(i[1], 16))
    #plaintext += chr(int(("0"*4+bin(int(i[0],16))[2::])[-4::]+("0"*4+bin(int(i[1],16))[2::])[-4::],2))
  return plaintext
if __name__ == '__main__':
  ciphertext = encrypt_hex("I love you")
  plaintext = decrypt_hex(ciphertext)
  print(f"{plaintext}: {ciphertext}")