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Why Prime number for Hashcode??

 
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Hi All,

I would like to know that why do we use prime number in Hash code implementation.
 
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I don't have deep knowledge on the implementation of hashing algorithms, but I know that using prime numbers minimizes collisions. See Wiki for a short explanation.
 
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It is more likely to produce slight differences in the right-hand bits of the number. Since HashMap etc use something analogous to hash % 16, hash % 32 etc, the lower-order bits are where differences are beneficial.
 
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We recently had a topic with a similar question and I wrote a long answer to it. Read it here.
 
pawan chopra
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Jesper Young wrote:We recently had a topic with a similar question and I wrote a long answer to it. Read it here.



Thanks Jesper I should have done some search on this before posting this question thanks alot great explanation.
 
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