What does it mean to "Know basic data structures and algorithms"?

Question

Career in IT

Good afternoon, in vacancies I often meet the phrase in the requirements or in the "will be a plus":
"Know the basic data structures and algorithms"

What is most often meant by this?

1. Knowledge of the device, how it works +-, the ability to implement after refreshing the details
2. Serrated knowledge, where you can come to the social services, and you are asked to implement the AVL tree, explain all its balancing cases and Asymptotic complexities, etc., etc.?

In general, how much do you need to memorize it?
Now I'm studying algorithms and data structures, but there is absolutely no desire to memorize them, and it's not easy to do so, + - I remember the implementation and details, but in order to implement it, you need to refresh the rules of structures and algorithms

Answer 1

What is most often meant by this?

Depends on the company and who will be interviewing.

In general, how much do you need to memorize it?

How to memorize algorithms correctly?

Answer 2

Watch who you go for. If starting positions, then these are data types, the main classes of the language. For algorithms, this is reading and writing to files, user interaction.
There is a lot to do with a particular language.
And yes, never cram theory in programming, otherwise you will sit in a puddle in practice. Write something.