pocketpy/python/_long.py
2023-12-30 13:57:51 +08:00

326 lines
8.9 KiB
Python

# after v1.2.2, int is always 64-bit
PyLong_SHIFT = 60//2 - 1
PyLong_BASE = 2 ** PyLong_SHIFT
PyLong_MASK = PyLong_BASE - 1
PyLong_DECIMAL_SHIFT = 4
PyLong_DECIMAL_BASE = 10 ** PyLong_DECIMAL_SHIFT
##############################################################
def ulong_fromint(x: int):
# return a list of digits and sign
if x == 0: return [0], 1
sign = 1 if x > 0 else -1
if sign < 0: x = -x
res = []
while x:
res.append(x & PyLong_MASK)
x >>= PyLong_SHIFT
return res, sign
def ulong_cmp(a: list, b: list) -> int:
# return 1 if a>b, -1 if a<b, 0 if a==b
if len(a) > len(b): return 1
if len(a) < len(b): return -1
for i in range(len(a)-1, -1, -1):
if a[i] > b[i]: return 1
if a[i] < b[i]: return -1
return 0
def ulong_pad_(a: list, size: int):
# pad leading zeros to have `size` digits
delta = size - len(a)
if delta > 0:
a.extend([0] * delta)
def ulong_unpad_(a: list):
# remove leading zeros
while len(a)>1 and a[-1]==0:
a.pop()
def ulong_add(a: list, b: list) -> list:
res = [0] * max(len(a), len(b))
ulong_pad_(a, len(res))
ulong_pad_(b, len(res))
carry = 0
for i in range(len(res)):
carry += a[i] + b[i]
res[i] = carry & PyLong_MASK
carry >>= PyLong_SHIFT
if carry > 0:
res.append(carry)
return res
def ulong_inc_(a: list):
a[0] += 1
for i in range(len(a)):
if a[i] < PyLong_BASE: break
a[i] -= PyLong_BASE
if i+1 == len(a):
a.append(1)
else:
a[i+1] += 1
def ulong_sub(a: list, b: list) -> list:
# a >= b
res = []
borrow = 0
for i in range(len(b)):
tmp = a[i] - b[i] - borrow
if tmp < 0:
tmp += PyLong_BASE
borrow = 1
else:
borrow = 0
res.append(tmp)
for i in range(len(b), len(a)):
tmp = a[i] - borrow
if tmp < 0:
tmp += PyLong_BASE
borrow = 1
else:
borrow = 0
res.append(tmp)
ulong_unpad_(res)
return res
def ulong_divmodi(a: list, b: int):
# b > 0
res = []
carry = 0
for i in range(len(a)-1, -1, -1):
carry <<= PyLong_SHIFT
carry += a[i]
res.append(carry // b)
carry %= b
res.reverse()
ulong_unpad_(res)
return res, carry
def ulong_divmod(a: list, b: list):
q = [0]
while ulong_cmp(a, b) >= 0:
ulong_inc_(q)
a = ulong_sub(a, b)
return q, a
def ulong_floordivi(a: list, b: int):
# b > 0
return ulong_divmodi(a, b)[0]
def ulong_muli(a: list, b: int):
# b >= 0
res = [0] * len(a)
carry = 0
for i in range(len(a)):
carry += a[i] * b
res[i] = carry & PyLong_MASK
carry >>= PyLong_SHIFT
if carry > 0:
res.append(carry)
return res
def ulong_mul(a: list, b: list):
N = len(a) + len(b)
# use grade-school multiplication
res = [0] * N
for i in range(len(a)):
carry = 0
for j in range(len(b)):
carry += res[i+j] + a[i] * b[j]
res[i+j] = carry & PyLong_MASK
carry >>= PyLong_SHIFT
res[i+len(b)] = carry
ulong_unpad_(res)
return res
def ulong_powi(a: list, b: int):
# b >= 0
if b == 0: return [1]
res = [1]
while b:
if b & 1:
res = ulong_mul(res, a)
a = ulong_mul(a, a)
b >>= 1
return res
def ulong_repr(x: list) -> str:
res = []
while len(x)>1 or x[0]>0: # non-zero
x, r = ulong_divmodi(x, PyLong_DECIMAL_BASE)
res.append(str(r).zfill(PyLong_DECIMAL_SHIFT))
res.reverse()
s = ''.join(res)
if len(s) == 0: return '0'
if len(s) > 1: s = s.lstrip('0')
return s
def ulong_fromstr(s: str):
if s[-1] == 'L':
s = s[:-1]
res, base = [0], [1]
if s[0] == '-':
sign = -1
s = s[1:]
else:
sign = 1
s = s[::-1]
for c in s:
c = ord(c) - 48
assert 0 <= c <= 9
res = ulong_add(res, ulong_muli(base, c))
base = ulong_muli(base, 10)
return res, sign
class long:
def __init__(self, x):
if type(x) is tuple:
self.digits, self.sign = x
elif type(x) is int:
self.digits, self.sign = ulong_fromint(x)
elif type(x) is float:
self.digits, self.sign = ulong_fromint(int(x))
elif type(x) is str:
self.digits, self.sign = ulong_fromstr(x)
elif type(x) is long:
self.digits, self.sign = x.digits.copy(), x.sign
else:
raise TypeError('expected int or str')
def __len__(self):
return len(self.digits)
def __add__(self, other):
if type(other) is int:
other = long(other)
elif type(other) is not long:
return NotImplemented
if self.sign == other.sign:
return long((ulong_add(self.digits, other.digits), self.sign))
else:
cmp = ulong_cmp(self.digits, other.digits)
if cmp == 0:
return long(0)
if cmp > 0:
return long((ulong_sub(self.digits, other.digits), self.sign))
else:
return long((ulong_sub(other.digits, self.digits), other.sign))
def __radd__(self, other):
return self.__add__(other)
def __sub__(self, other):
if type(other) is int:
other = long(other)
elif type(other) is not long:
return NotImplemented
if self.sign != other.sign:
return long((ulong_add(self.digits, other.digits), self.sign))
cmp = ulong_cmp(self.digits, other.digits)
if cmp == 0:
return long(0)
if cmp > 0:
return long((ulong_sub(self.digits, other.digits), self.sign))
else:
return long((ulong_sub(other.digits, self.digits), -other.sign))
def __rsub__(self, other):
if type(other) is int:
other = long(other)
elif type(other) is not long:
return NotImplemented
return other.__sub__(self)
def __mul__(self, other):
if type(other) is int:
return long((
ulong_muli(self.digits, abs(other)),
self.sign * (1 if other >= 0 else -1)
))
elif type(other) is long:
return long((
ulong_mul(self.digits, other.digits),
self.sign * other.sign
))
return NotImplemented
def __rmul__(self, other):
return self.__mul__(other)
#######################################################
def __divmod__(self, other):
if type(other) is int:
assert self.sign == 1 and other > 0
q, r = ulong_divmodi(self.digits, other)
return long((q, 1)), r
if type(other) is long:
assert self.sign == 1 and other.sign == 1
q, r = ulong_divmod(self.digits, other.digits)
assert len(other)>1 or other.digits[0]>0
return long((q, 1)), long((r, 1))
raise NotImplementedError
def __floordiv__(self, other):
return self.__divmod__(other)[0]
def __mod__(self, other):
return self.__divmod__(other)[1]
def __pow__(self, other: int):
assert type(other) is int and other >= 0
if self.sign == -1 and other & 1:
sign = -1
else:
sign = 1
return long((ulong_powi(self.digits, other), sign))
def __lshift__(self, other: int):
assert type(other) is int and other >= 0
x = self.digits.copy()
q, r = divmod(other, PyLong_SHIFT)
x = [0]*q + x
for _ in range(r): x = ulong_muli(x, 2)
return long((x, self.sign))
def __rshift__(self, other: int):
assert type(other) is int and other >= 0
x = self.digits.copy()
q, r = divmod(other, PyLong_SHIFT)
x = x[q:]
if not x: return long(0)
for _ in range(r): x = ulong_floordivi(x, 2)
return long((x, self.sign))
def __neg__(self):
return long((self.digits, -self.sign))
def __cmp__(self, other):
if type(other) is int:
other = long(other)
elif type(other) is not long:
return NotImplemented
if self.sign > other.sign:
return 1
elif self.sign < other.sign:
return -1
else:
return ulong_cmp(self.digits, other.digits)
def __eq__(self, other):
return self.__cmp__(other) == 0
def __lt__(self, other):
return self.__cmp__(other) < 0
def __le__(self, other):
return self.__cmp__(other) <= 0
def __gt__(self, other):
return self.__cmp__(other) > 0
def __ge__(self, other):
return self.__cmp__(other) >= 0
def __repr__(self):
prefix = '-' if self.sign < 0 else ''
return prefix + ulong_repr(self.digits) + 'L'