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