If you are not writing code, you should be reading! There are many books, but it doesn't exactly. smatter which book you read, as long as you can justify and digest it. However, it is probably best to skip those that cause you to struggle more than understand.
For example, you decide to pick up CLRS because you're interested in strengthening your understanding of algorithms, and it was recommended on this list.
You start reading it but you find that you are struggling with most of the reading because you don't understand half of the writing. If you're getting stuck on the lexicon, and find yourself constantly looking up terms or you're confused as to why the proof is using a geometric series, you need to take a step back.
Take note of what you struggled with and look for a book that will cover this. Usually, it's a prerequisite topic. In the previous example, to understand proofs, it'd be discrete mathematics. It would help to look for a book on this.
Here are some books we recommend, compiled from other recommendations lists and books our own members had mentioned in the server before.