For sets that are plausibly sometimes going to be small where you're going to do a lot of membership checks, you can speculatively add a 64 bit bloom filter with a trivial hash function.

This sounds really stupid, but the cost of doing this is so small you can do it as a gamble. If it doesn't work out you've added like 10ns to your insertions and membership checks, but when it does work out, you can save an incredible amount of work.

It appears that perfect hash is the one that works the best for my use case.

I probably could have made $100,000,000 if I had made a different choice there.

After being aware of bloom filters for a while it was quite satisfying to organically find a real use for one that was such an improvement.

All three concepts are key in understanding operations of complex distributed systems.

It will demonstrate why the answer is always "maybe it's in the set!" instead of "yes".

> When you add a string, you can see that the bits at the index given by the hashes are set to 1. I've used the color green to show the newly added ones

because all I saw was the content text of "Your set:" changing, no bits, no colors. It took me trying a different browser and then scrolling up and down to realize that it's the visualization two paragraphs above that was changing.

There is a only bloom filter calculator that lets you just mess arpund with parameters

This one compares bloom and coockoo filters, so it adds a little more information.