As a brainlet who has gone through CS courses I can only solve up to 6 of these in 2 hours?
I cant figure out a proof of correctness for any of my solutions.
Got stuck on pic related.

Goal is get the black pointer on the same spot as the white star by building functions.
uncolored functions work on all spaces.
colored functions work only on colored spaces( basically an if statement).
The commands are move forward, rotate left, rotate right, call function f1, call function f2.

Questions are from codeam dot nl which promotes itself to complete beginners.