I would like a book recommendation.
Could you kindly point out some Olympiad style problem compilations, with relatively easier problem, but escalating with time. Topics must include Algebra, Geometry, Combinatorics and Elementary Number Theory.
As of now, I posses The USSR Problem Book, which is quite good for Algebra and Elementary Number Theory but lacks Geometry and Combinatorics (counting problems, basically). I have Sharygin's Problems in Plane Geometry, which suffices. But still no problem books in Combinatorics.
If you recommend a book with all of the above that would contribute to my problem solving skills, I would be grateful. And the book should have TONS of problems, literally.
Thanks, y'all!!!