i used numpy, but its clear you dont need to, and the solutions that dont use packages are still clean and fast

this felt pretty easy actually. key question to work out is what you're looping over, and how

really challenging, great little kata. as with others, the decryption function is the mind killer. creativity with indexing and slicing is the key ;)

in python at least, pretty simple. suggest doing some reading up front on Cartesian planes

nice little exercise. at least a couple of different ways to do it, and nothing tricky. looks like historically the tests might have needed some attention, but seem fine now (python)

tricky, but not very enjoyable

nice entry point to binary trees

in the end i opted for a very dirty fix to manage the string length issue. not my finest work

that was totally next level; loads of fun. trickiest part was handling longer sequences of numbers. my solution was neolithic; others used far more elegant approaches.

like most things from this author, well calibrated and with multiple solutions

maybe a link to some reading? this is potentially one of the first BT kata people will do. would be good to use it as a deliberate teaching moment

lots of energy focused here on the edge cases. it may be plodding, but i chose to handle those manually. life's too damn short :)

well calibrated

took me a year to solve my own problem :) Hint: the arg inputs of the function need to handle variable numbers of args.

probably a 7?