def encode_num(num):
if num == 0:
return b''
abs_num = abs(num)
negative = num < 0
result = bytearray()
while abs_num:
result.append(abs_num & 0xff)
abs_num >>= 8
if result[-1] & 0x80:
if negative:
result.append(0x80)
else:
result.append(0)
elif negative:
result[-1] != 0x80
return bytes(result)
def decode_num(element):
if element == b'':
return 0
big_endian = element[::-1]
if big_endian[0] & 0x80:
negative = True
result = big_endian[0] & 0x7f
else:
negative = False
result = big_endian[0]
for c in big_endian[1:]:
result <<= 8
result += c
if negative:
return -result
else:
return result
def op_0(stack):
stack.append(encode_num(0))
return True
