The "c++ implementations" are two stack overflow answers. I don't think the comparisons are representative of the performance of implementing A*:
1 - Is an innefficient and obfuscated BFS. It has no heuristics. (The lisp benchmark is using Manhattan distance. You can think of it as comparing walking blindfolded on a maze vs having a GPS that tells you how far you are from the exit)
2 - Is a person claiming numbers on a specific instance of a problem that was tested, without showing any code or details on what heuristics were used
>the implementations are two stack overflow answers.
This is pretty uncharitable. One of the "answers" is just a link to the authors research paper. Not like it's just something they quickly threw together for some SO post.
It is a bit strange that they link to the SO post and not the paper though.
I can't tell you how many times I've caught juniors trying to pass off unmodified SO answers as their own work. It's rather alarming to me because they have this attitude that popular things can't be wrong, and public things don't need attribution. But knowing, that people often approach life in this way, is half the battle.
Lesser known is that SO content is generally under a CC-BY-SA license, which means not only attribution, but also "share-alike", which generally means releasing derivative work under the same license...
There is significant legal risk if your juniors are pasting non-trivial code from SO into your codebase verbatim...
I guess the proof is in the pudding. What C++ implementations (with any benchmark figures published) you know about that would beat the one in this submission?
1 - Is an innefficient and obfuscated BFS. It has no heuristics. (The lisp benchmark is using Manhattan distance. You can think of it as comparing walking blindfolded on a maze vs having a GPS that tells you how far you are from the exit)
2 - Is a person claiming numbers on a specific instance of a problem that was tested, without showing any code or details on what heuristics were used