I've been reading through CtCI and my data structure and other knowledge is so rusty that I'm having trouble reading CtCI, does anyone have recommendation for a book/books that goes over the basic concepts as opposed to how they're used in an interview? FWIW I am using an older version and the newer ones might have an explanation, perhaps I should get the newer version of CtCI?
Elements of Programming Interviews is really easy to follow. Definitely not simple, but it’s more accessible than I remember CTCI being.
Look at geeksforgeeks.com. they've most ctci solutions explained.