i've being trying to learn how to do it myself. I'm a beginner too and I always seeing that this is how the most skilled do, and it makes a lot of sense. The trick here is to learn how to think and do it that way. Just like all the learning so far, it's practice

Depends how much experience you have. This is not beginner friendly, but since there is very little logic in there, that's how you would write the solution for this kind of problem once you are reasonnably skilled in the language.

I've noticed that a lot of ppls submitted codes, in which everything was pressed in a single line. Is that how you do it? Personally I think it is not really clean and makes it less comprehensible. But that's just from my perspective as a beginner.