Hello CF community, in this blog post I tried to gather the Questions I've solved and enjoyed them most of them are really teaching and worth spending hours of time on them Hope you enjoy

Note that to solve these problems you need no knowledge except:
9th grade math, a little bit number theory, sorting, elementary dp, elementary bs, set, stack, queue, map

Good luck and hope you enjoy them

EDIT: I added maybe a few problems, I ran out of beautiful problems, unfortunately, maybe suggest in the comments