[Morse encoding] codewar challenge: morse encoding #python #algorithm #challenge

.py

def convert_complement_to_dec(str):
  if str[0] == '1':
    reversed_str = ''
    for bit in str[1:]:
      reversed_str += '1' if bit == '0' else '0'
    return -1 * (int('0b' + reversed_str, 2) + 1)
  return int('0b' + str, 2) 

def convert_dec_to_complement(val):
  val_bin = bin(val)
  if val >= 0: return '0' + '0' * (32 - len(val_bin) + 3) + bin(val)[2:]
  tmp_reverse = ''
  tmp = '1' * (32 - len(val_bin) + 3 - 1) + val_bin[3:]
  for bit in tmp:
    tmp_reverse += '1' if bit == '0' else '0'
  tmp_reverse_1 = bin(int('0b' + tmp_reverse, 2) + 1)[2:]
  return '1' + '0' * (32 - len(tmp_reverse_1) - 1) + tmp_reverse_1
  

class Morse:
  alpha={
  'A': '10111',
  'B': '111010101',
  'C': '11101011101',
  'D': '1110101',
  'E': '1',
  'F': '101011101',
  'G': '111011101',
  'H': '1010101',
  'I': '101',
  'J': '1011101110111',
  'K': '111010111',
  'L': '101110101',
  'M': '1110111',
  'N': '11101',
  'O': '11101110111',
  'P': '10111011101',
  'Q': '1110111010111',
  'R': '1011101',
  'S': '10101',
  'T': '111',
  'U': '1010111',
  'V': '101010111',
  'W': '101110111',
  'X': '11101010111',
  'Y': '1110101110111',
  'Z': '11101110101',
  '0': '1110111011101110111',
  '1': '10111011101110111',
  '2': '101011101110111',
  '3': '1010101110111',
  '4': '10101010111',
  '5': '101010101',
  '6': '11101010101',
  '7': '1110111010101',
  '8': '111011101110101',
  '9': '11101110111011101',
  '.': '10111010111010111',
  ',': '1110111010101110111',
  '?': '101011101110101',
  "'": '1011101110111011101',
  '!': '1110101110101110111',
  '/': '1110101011101',
  '(': '111010111011101',
  ')': '1110101110111010111',
  '&': '10111010101',
  ':': '11101110111010101',
  ';': '11101011101011101',
  '=': '1110101010111',
  '+': '1011101011101',
  '-': '111010101010111',
  '_': '10101110111010111',
  '"': '101110101011101',
  '$': '10101011101010111',
  '@': '10111011101011101',
  ' ': '0'}
  sorted_alpha_tuple = sorted(alpha.items(), key=lambda kvt: len(kvt[1]), reverse=True)
  @classmethod
  def find_matching_alpha(cls, binary_str):
    for alpha_code in Morse.sorted_alpha_tuple:
      if alpha_code[1] == binary_str[:len(alpha_code[1])]:
        return alpha_code[0], binary_str[len(alpha_code[1]) + 3:]
    return None
      
  @classmethod
  def encode(self,message):
    chars = list(message)
    binary_str = ''
    for char in chars:
      binary_str += Morse.alpha[char] + '000'
    binary_str += '0' * (32 - (len(binary_str) % 32))
    turn = 0
    result = list()
    while True:
      if (turn + 1) * 32 > len(binary_str): break
      tmp = convert_complement_to_dec(binary_str[turn * 32:(turn + 1) * 32])
      result.append(tmp)
      turn += 1
    return result
    
  @classmethod
  def decode(self, array):
    binary_str = ''
    for dec in array:
      binary_str += convert_dec_to_complement(dec)
    result = ''
    while binary_str:
      tmp, binary_str = Morse.find_matching_alpha(binary_str)
      result += tmp
    return result.strip()