Great kata series to learn through, thanks.

wait what is there a non-math solution?

To me a best practice is code that is self explanatory, I look at this code and while it is smart I would have no idea that it returns a sum of all numbers up to n. Whereas if I look at a loop that traverses all the numbers and sums them up - it's clear what the code does.

can you explain this....

Thanks for the kata! I liked how it naturally guides you toward a simple, readable solution and makes you think about pair ordering without overcomplicating things. Fun and well‑designed 👍

That is really cool. Way better than mine.

nice

approved

Great kata on algorithms to learn with.

adding #include <fmt/ranges.h> to the sample tests fixed it... I have no idea why

C++ sample tests don't compile

Amazing example of dynamic programming.

Brain-time optimization

Yes because the Gauß formula is the most efficient solution.