diff options
Diffstat (limited to 'rfc1982_serial_number.py')
| -rw-r--r-- | rfc1982_serial_number.py | 28 |
1 files changed, 19 insertions, 9 deletions
diff --git a/rfc1982_serial_number.py b/rfc1982_serial_number.py index 8f558bf..2d884a2 100644 --- a/rfc1982_serial_number.py +++ b/rfc1982_serial_number.py @@ -3,11 +3,14 @@ class Serial: def __init__(self, val): - self._val = int(val) & (2**32) + self._val = int(val) % 2**32 def __int__(self): return self._val + def __str__(self): + return str(int(self)) + def __add__(self, val): return Serial(self._val + int(val)) @@ -19,24 +22,31 @@ class Serial: def __lt__(self, other): return self != other and ( - (self._val < other._val and other._val - self._val < 2**31) or - (self._val > other._val and self._val - other._val > 2**31)) + (int(self) < int(other) and int(other) - int(self) < 2**31) or + (int(self) > int(other) and int(self) - int(other) > 2**31)) def __gt__(self, other): return self != other and ( - (self._val < other._val and other._val - self._val > 2**31) or - (self._val > other._val and self._val - other._val < 2**31)) + (int(self) < int(other) and int(other) - int(self) > 2**31) or + (int(self) > int(other) and int(self) - int(other) < 2**31)) if __name__ == "__main__": from random import randint for test in range(100): - i1 = randint(0, 2**32-1) - i2 = randint(0, 2**32-1) - - print(i1, i2) + i1 = Serial(randint(0, 2**32-1)) + i2 = Serial(randint(0, 2**32-1)) assert i1 == i2 or \ (i1 < i2 and not (i1 > i2)) or \ (i1 > i2 and not (i1 < i2)) or \ int(i1) & int(i2) == 0x80000000 + + if i1 == i2: + print(f"{int(i1):10d} == {int(i2):10d}, how did that happen?") + elif i1 < i2: + print(f"{int(i1):10d} => {int(i2):10d}, can do it in one jump") + else: + i3 = i1 + (2**31 - 2) + print(f"{int(i1):10d} => {int(i2):10d}, need to wrap, i3 value {i3}") + assert i1 < i3 and i3 < i2 |