Thanks for the reference. Another algorithms text -- though Haskell centric -- that provides solutions is Algorithm Design With Haskell [1]. The exhaustive Combinatorial Mathematics by Douglas West [2] provides hints at least. These are advanced texts though. Another source of solved problems are "problems in" books. Dover offers affordable titles like Fifty Challenging Problems in Probability [3]. There are other classics like Combinatorial Problems and Exercises [4] or Proofs from the Book [5], all with solved exercises.

[1] https://www.cambridge.org/core/books/algorithm-design-with-h...

[2] https://faculty.math.illinois.edu/~west/

[3] https://store.doverpublications.com/0486653552.html

[4] https://www.ams.org/books/chel/361/

[5] https://www.springer.com/gp/book/9783642008566