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KrzysztofCiba/popcnt16b.py

Created June 9, 2013 19:54
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popcnt16k.py
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popcnt16b.py
__bc16b = [ 0 ] * (256*256)
for i in range(256*256):
__bc16b[i] = ( i & 1 ) + __bc16b[i/2]
def popcnt16b( arg ):
""" popcnt using 16bits loom up table """
return sum( [ __bc16b[( arg >> i ) & 65535 ] for i in range( 0, arg.bit_length(), 16 ) ] )
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