For Python, VS Code and Jupyter Lab. I used Sublime Text 3 previously but have found VS Code to be easier to set up and better supported over time. I do miss how fast and lightweight Sublime is this compared to VS Code though so I still use ST4 as a general text editor.

For Excel VBA (ugh), pretty much have to use the built in one as there doesn’t seem to be any alternative.

Oh yeah. This is quite fun, though once you hit level 4/5 some problems require fairly advanced algorithms / mathematics. One of the problems I gave up on solving on my own required knowledge of Polyas enumeration theorem to solve. Fortunately or unfortunately you can find some answers online, otherwise I would’ve never even known such a theorem existed.

For the tougher problems, expect a lot of graph theory / combinatorics, which I guess is the nature of Googles challenges as a search engine.