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roylee0704/prehash_tuple.py

Created May 15, 2016 11:21
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python prehash implementation of tuple type. (simplified version)
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prehash_tuple.py
def hash(tuple):
mult = 1000003
x = 0x345678
for index, item in enumerate(tuple):
x = ((x ^ hash(item)) * mult) & (1<<32)
mult += (82520 + (len(tuple)-index)*2)
return x + 97531
@MartinThoma
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Do you know where the numbers come from? For example, why is 97531 added? Why not 97530 or 97529? Why not 13933?

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