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This is a complete non-sequitur, but I checked out your web page. I love the Curious George image. My daughter has been deeply into the Curious George episodes for the past couple of months, and I don't think I've seen him show up in many other places besides kids' shows :D
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I think of Curious George Goes to a Chocolate Factory when I fire up Claude Code.
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Such a good show. My kids grew up on it!
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What do you mean by "galactic"?
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Galactic algorithms have such huge constants they figuratively need a galaxy-sized computer and/or galaxy-sized problem, to have any advantage over the normal solutions. Imagine a generic sorting algorithm in O(n) that had a constant of 10^92 **. Technically superior but in practice unusable.

** Yes, I know that's proven to be impossible.

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There are realistic situations where galactic O(n) sorting algorithms exist, right? 32-bit integers can be sorted in O(n) using 2^32 words of memory, using bucket sort[1].

If objects have a maximum size of 4 GB (= 2^35 bits), then arbitrary objects can be sorted in O(n) using 2^2^35 bits of memory.

[1] https://en.wikipedia.org/wiki/Bucket_sort

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Right, that's why I wrote "a generic sorting algorithm". Your case adds the integer limit which allows it to avoid O(nlogn) minimum.
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You can use Radix sort https://en.wikipedia.org/wiki/Radix_sort to lower the memory requirement for limited bit-width integers. But there are more practical o(n log n) methods for sorting integers.
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Well optimized radix sorts are actually pretty fast (assuming you have the proper fallbacks to quicksort/insertion sort to deal with medium/small sizes)
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Do we know they are galactic?
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> A galactic algorithm is an algorithm with state-of-the-art theoretical (asymptotic) performance, but which is not used due to practical constraints.

Yes, I think we can pretty safely say that the algorithm in the paper is not used due to practical constraints. This is a subjective judgment, but pretty clear from the paper that the algorithms aren't practical to apply.

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