# GynvaelEN mission 004

# cat mission_04.py
def hex2bin(h):
 binary = ''
 for i in range(0, len(h), 2):
  byte = u[i:i + 2]
  binary += format(int(byte, 16), '08b')
 return binary

def decode(u):
 lu = len(u)
 if lu == 2:
  return u.decode('hex')
 elif lu  == 4:
  binary = hex2bin(u)
  r = binary[3:8] + binary[10:]
  return chr(int(r, 2))
 elif lu  == 6:
  binary = hex2bin(u)
  r = binary[4:8] + binary[10:16] + binary[18:]
  return chr(int(r, 2))
 elif lu  == 8:
  binary = ''
  binary = hex2bin(u)
  r = binary[5:8] + binary[10:16] + binary[18:24] + binary[26:]
  return chr(int(r, 2))

message = 'E0818F766572C1ACE081AFE081AEC1A7E080A0E08195C194E081862DE080B8E080A0F08081B7C1A17320C1B3F08081B563C1A820E081A1F08080A0E081A6F08081B5F08081AE20E081A6E081A5F08081A1C1B475E081B2E081A5F08080AE'

result = ''

i = 0

while i < len(message):
 byte = int(message[i:i+2], 16)
 binary = format(byte, '08b')
 if binary[0] == '0':
  j = 2
 elif binary[0:3] == '110':
  j = 4
 elif binary[0:4] == '1110':
  j = 6
 elif binary[0:5] == '11110':
  j = 8
 u = message[i:i + j]
 i += j
 result += decode(u)

print result
# python mission_04.py
Overlong UTF-8 was such a fun feature.

Source

https://www.youtube.com/watch?v=iwRSFlZoSCM (1:26:42)

Reference

https://es.wikipedia.org/wiki/UTF-8#Codificaci.C3.B3n_de_los_caracteres