I have big love for PE. I've learnt so much in the process of trying to solve some of these problems. In particular, number theory and data structures are two fields that I have come to love almost entirely because of this website. I did a random selection of the first 200 problems on my own about a decade ago but ran out of steam as the problems got harder.
Recently, however, I introduced it at work as a way of encouraging the team I manage to work collaboratively. We have a fortnightly catch up where we talk through solutions, pick new problems (we have a script that randomly picks an easy, medium and hard problem, which has become an exciting ritual), and then we have an initial discussion about each of the new problems.
It's a good way to foster group work. It's also a great way to introduce people to using version control and pull-requests in a non-scary way!
Most PE problems are more math than data-structure based. There are plenty of number theory problems, but lots of other areas as well, especially combinatorics and probability. I’ve learned about many more niche areas, like impartial games and chromatic polynomials, via PE.
But there are definitely more CS-oriented problems. I can recall problems solved by using segment trees, Aho-Corasick, simple parsing, etc. And lots and lots of dynamic programming.
Also, working your way through the first 100 problems will require writing code to evaluate poker hands and solve Sudoku boards.
Recently, however, I introduced it at work as a way of encouraging the team I manage to work collaboratively. We have a fortnightly catch up where we talk through solutions, pick new problems (we have a script that randomly picks an easy, medium and hard problem, which has become an exciting ritual), and then we have an initial discussion about each of the new problems.
It's a good way to foster group work. It's also a great way to introduce people to using version control and pull-requests in a non-scary way!