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__all__ = ["popCount", "bit_count", "bit_indices"]
try:
bit_count = int.bit_count
except AttributeError:
def bit_count(v):
return bin(v).count("1")
"""Return number of 1 bits (population count) of the absolute value of an integer.
See https://docs.python.org/3.10/library/stdtypes.html#int.bit_count
"""
popCount = bit_count # alias
def bit_indices(v):
"""Return list of indices where bits are set, 0 being the index of the least significant bit.
>>> bit_indices(0b101)
[0, 2]
"""
return [i for i, b in enumerate(bin(v)[::-1]) if b == "1"]
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