如何使用每个字母2个字母字符将字符串转换为自定义基

Question

下面的函数使用base16字母表'0123456789ABCDEF'将数字255 (base10)转换为'FF' (base16)

我很难弄清楚如何修改函数，使它们在每个字母中使用2个字母，这样数字255 (base10)将使用修改后的base16字母'x0x1x2x3x4x5x6x7x8x9xAxBxCxDxExF'转换为'xFxF' (base16)

def v2r(num, alphabet):
  """Convert base 10 number into a string of a custom base (alphabet)."""
  alphabet_length = len(alphabet)
  result = ''
  while num > 0:
    result = alphabet[num % alphabet_length] + result
    num  = num // alphabet_length
  return result


def r2v(data, alphabet):
  """Convert string of a custom base (alphabet) back into base 10 number."""
  alphabet_length = len(alphabet)
  num = 0
  for char in data:
    num = alphabet_length * num + alphabet[:alphabet_length].index(char)
  return num

base16 = v2r(255, '0123456789ABCDEF')
base10 = r2v(base16, '0123456789ABCDEF')
print(base16, base10)
# output: FF 255

# base16 = v2r(255, 'x0x1x2x3x4x5x6x7x8x9xAxBxCxDxExF')
# base10 = r2v(base16, 'x0x1x2x3x4x5x6x7x8x9xAxBxCxDxExF')
# print(base16, base10)
# output: xFxF 255

Answer 1

我建议在开始计算之前删除“x”，因此将add作为函数的第一行

alphabet=alphabet.replace('x','')

因此，您的函数将同时适用于“FFF”或“XF”两种系统

def v2r(num, alphabet):
  """Convert base 10 number into a string of a custom base (alphabet)."""
  alphabet=alphabet.replace('x','') ### added
  alphabet_length = len(alphabet)
  result = ''
  while num > 0:
    result = alphabet[num % alphabet_length] + result
    num  = num // alphabet_length
  return result


def r2v(data, alphabet):
  """Convert string of a custom base (alphabet) back into base 10 number."""
  alphabet=alphabet.replace('x','') ### added
  alphabet_length = len(alphabet)
  num = 0
  for char in data:
    num = alphabet_length * num + alphabet[:alphabet_length].index(char)
  return num