Knowing how popular algorithms or exotic data structures work are not something you should need to know to work at a tech company. You should know what an algorithm is, and should be able to come up with simple ones on your own, like a greedy one. You should also know about basic data structures that are pretty common, like hashtables, queues, or stacks. But specific algorithms like Dijkstra, A* and more advanced ones are not things you'd need to memorize: you'll have a reference for this.