concrete mathematics
https://www.analyticsinsight.net/tech-news/top-10-books-to-learn-data-structures-and-algorithms
https://bookauthority.org/books/beginner-algorithms-books
https://shepherd.com/best-books/for-actually-learning-how-to-design-algorithms
https://bookauthority.org/books/beginner-combinatorics-books
https://bookauthority.org/books/beginner-graph-theory-books
https://numberdyslexia.com/graph-theory-books-for-beginners/