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by charleslmunger 794 days ago
>Do not implement your own fancy data structures: instead use the Standard Template Library. I use STL map, set, and vector all of the time and they remove the need for most other data-structures.

Don't the STL tree and map data structures have notoriously poor performance?
1 comments
roeles 794 days ago
I don't think you can make general statements about STL. I have seen a Pi4 outperform a core i7 in very specific cases. That was really unexpected.

In other cases I saw a lot of runtime spent on std::map.

I think the best advice is: learn to use a profiler.

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tsegratis 792 days ago
From memory, std::map is comparatively slow because the spec requires pointers to indices to be stable. In practice it is slow; see khash and many others

Personally i don't think this matters too much; you're using c/c++; you're already fast

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