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Hashcode method implementation  RSS feed

 
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In the implementation of hashcode methods, I have generally observed that it uses the number 31 in calculations; what could be the reason behind using this number why not other prime number such as 37, 41, 43 etc.
 
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Not a “beginning” questions: let's try the “general computing” forum.

People used to use different prime numbers, 13, 17, 19, 23 etc., in order. The idea of prime numbers is to move as much of the variation to the right‑hand end of the result. I don't know whether it si that 31 does it as efficiently as any other prime number, and can be optimised by the compiler toDon't try implementing that optimisation yourself.
 
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