As someone who does not have a computer science degree, Interview Cake was an amazing service to help fill those knowledge gaps. I highly recommend it to all my bootcamp friends (and CS-degree friends) who are on the job hunt.
I first used it 3 years ago when I was fresh out of bootcamp. It was amazing back then, but they've added a lot more helpful content and have built-in test cases for each algorithm now.
They really do a great job of "showing you the door" to the answer, eventually revealing the best solution (taking space and time complexity into consideration).
Since practicing data structures and algorithms is nobody's favorite thing, I like how they keep things light with clever scenarios for each algorithm. For instance, the combining sorted arrays problem has a "selling girl scout cookies" backstory, and subsequent related variable names.
It's down from it's regular $249 for 12 months of access, as well as a free trial, but if for whatever reason you hate it, they've got a money-back guarantee. ✌️
Not an endorsement. I'm just a regular guy trying to help his fellow job-hunting dev.