in reply to Re: RFC: Is there a solution to the flaw in my hash mechanism? (And are there any others?)
in thread RFC: Is there a solution to the flaw in my hash mechanism? (And are there any others?)

Use the value at the hash collision to get the offset for the next hash key.

Problem. The value giving the trouble is 0; so the value at the hash collision can be 0; and 0 + 0 == 0 :)

Of course, it won't always be zero. Any multiple of the Prime size will mod to a hash of 0; but is still means that if a true 0 value arises, the thing disappears up it you know where.

Having spent the last 3 days running some long-running, large scale simulations; I'm satisfied that the benefits of the declustering affect of the i+1 = ( i + prime ) % prime scheme are real, and outweigh the need to have an if( !i ) { //take a different path conditional test in the inner loop.

I'm still trying a couple of things for that other path; but adding prime/2 seems as good as any other thing I've thought of.


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