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d Zy)a Python implementations of some algorithms for use by longobject.c.
The goal is to provide asymptotically faster algorithms that can be
used for operations on integers with many digits. In those cases, the
performance overhead of the Python implementation is not significant
since the asymptotic behavior is what dominates runtime. Functions
provided by this module should be considered private and not part of any
public API.
Note: for ease of maintainability, please prefer clear code and avoid
"micro-optimizations". This module will only be imported and used for
integers with a huge number of digits. Saving a few microseconds with
tricky or non-obvious code is not worth it. For people looking for
maximum performance, they should use something like gmpy2. Nc t j d di fd fdt j 5 }t j |_ t j
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z }|| < |S )zReturn D(2)**w and store the result. Also possibly save some
intermediate results. In context, these are likely to be reused
across various levels of the conversion to Decimal. get)wresulttw2BITLIMD2memw2pows ;/BuggyBox/python/3.12.0/bootstrap/lib/python3.12/_pylong.pyr z int_to_decimal.<locals>.w2pow' sx ggaj F )F{QQ# "1q5z/!Q.!V
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C*O CF r c X | j j dd } t | S )zoAsymptotically fast version of PyLong_FromString(), conversion
of a string of decimal digits into an 'int'._ )rstripreplacer; )r8 s r int_from_stringrA s'
3#A Q r c t j d| }|s t d t |j d }|j d dk( r| }|S )zBAsymptotically fast version of decimal string to 'int' conversion.z\s*([+-]?)([0-9_]+)\s*z&invalid literal for int() with base 10r r -)rematch
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z | fS )aR Divide a 2n-bit nonnegative integer a by an n-bit positive integer
b, using a recursive divide-and-conquer algorithm.
Inputs:
n is a positive integer
b is a positive integer with exactly n bits
a is a nonnegative integer such that a < 2**n * b
Output:
(q, r) such that a = b*q+r and 0 <= r < b.
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z z fd| r | dt S )aR Decompose non-negative int a into base 2**n
Input:
a is a non-negative integer
Output:
List of the digits of a in base 2**n in little-endian order,
meaning the most significant digit is last. The most
significant digit is guaranteed to be non-zero.
If a is 0 then the output is an empty list.
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Ha A a4Kr c |dk( rt |dk rt | | \ }}|| fS | dk rt | | \ }}| || z fS t | | S )zAsymptotically fast replacement for divmod, for 'int'.
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