[110jawefopiwa]

> Advent of Code, are so heavily focused on making clever use of math, data structures and algorithms

I've done a fair amount of Advent of Code and I wouldn't say it's at all "focused" on this. The vast majority of the questions use hash tables and graph traversal as the full extent of their use of math/DS/algos.

There's always one or two puzzles every year that require some particular math/CS insight but most of them just need you to know BFS and/or how to write a parser.

Your examples are also not bad, but they seem to be primarily concerned with "getting familiar with a new programming language" in the context of writing a web server, which is one of the parts of programming I try to stay away from. Most of your examples require less familiarity with the language's features and more with libraries you might use, which is less interesting to me personally (then again, I'm a PL fan and I write compilers for a living).

Meanwhile, I like AoC because I've used language features to take the fairly straightforward potential implementations and write them more elegantly in the language I choose. e.g. I use Monads in Haskell, or use Rust's easy threading to parallelize solutions, etc.

For me, learning a new programming language is largely uninteresting unless it changes the fundamental "shape" I think in, rather than what the exact names of the libraries I use change to. e.g. I already know Java so I'm not really going to bother "learning" C#. I already know Python so I don't really bother diving deep into Ruby, etc. However, I learn Haskell, Rust, Forth, Erlang, Scheme, etc.

[fulafel]

AoC is still is algorithms and data structures: there's minimal interaction with the outside world, just solving the problem for the input data. It's just about coming up with the algorithm yourself instead of applying fancy well-known ones.

[cabidaher]

> just solving the problem for the input data

I think a lot of people here would be surprised how much of a step up this is from classic leetcode or DSA stuff. I have been involved in introducing people to AoC and helping them and the amount of people who have basic knowledge of algorithms but struggled to parse the input from a file was a little shocking to me at first. Of course, I do not blame anyone for not knowing something, classic academic courses can be misguided sometimes.

This doesn't negate the fact that there is somewhat of a lack in problems with more outside world interaction and it would be cool to see more of that.

[wodenokoto]

> It's just about coming up with the algorithm yourself instead of applying fancy well-known ones.

Isn’t that the whole fun?

[legends2k]

Exercism.io does what you want? It has language tracks and each track has questions geared to seal your understanding of some language concept. It also has it gamified by building a community around it and folks comparing their solutions.