Is there implementation for monotonically increasing hash function:
given x,y,z are monotonically increasing the f(x,y,z) will be monotonically increasing ?
Update
We can assume x,y,x are positive integers and the method result is long
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Alex Stanovsky
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4https://softwareengineering.stackexchange.com/questions/216538 – Robert Harvey Mar 26 '19 at 15:46
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1https://en.wikipedia.org/wiki/Hash_table#Monotonic_keys – Robert Harvey Mar 26 '19 at 15:47
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Thanks, I was looking for open source implementation. Bitwise operations will be my second try – Alex Stanovsky Mar 26 '19 at 15:49
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Not only is there no implementation, it's not even possible. Three java positive ints equals 93 bits of input, and a long is 64 bits of output. So you are at war with the pigeonhole principle, an invincible opponent. – President James K. Polk Mar 26 '19 at 17:47
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@JamesKPolk: Hashes have never required the input to have the same number of bits as the hash, and yes, you're going to pigeonhole. I would consider that a feature, not a bug. – Robert Harvey Mar 26 '19 at 18:39
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1@RobertHarvey: Let me try again. What does it even mean for a triple (x,y,z) to be monotonically increasing? – President James K. Polk Mar 26 '19 at 20:04