Without the 0x
prefix, you need to specify the base explicitly, otherwise there’s no way to tell:
x = int("deadbeef", 16)
With the 0x
prefix, Python can distinguish hex and decimal automatically:
>>> print(int("0xdeadbeef", 0))
3735928559
>>> print(int("10", 0))
10
(You must specify 0
as the base in order to invoke this prefix-guessing behavior; if you omit the second parameter, int()
will assume base-10.)