Your comment led me down a bit of a rabbit hole and I found this on Wikipedia:

When writing in languages such as Danish and Norwegian, where the empty set character may be confused with the alphabetic letter Ø (as when using the symbol in linguistics), the Unicode character U+29B0 ⦰ REVERSED EMPTY SET may be used instead.

It also mentions what you are alluding to:

In the past, “0” (the numeral zero) was occasionally used as a symbol for the empty set, but this is now considered to be an improper use of notation.

And, as a programmer, don’t get me started on nulls…or undefined…or truthyness.

As a Norwegian, I find it annoying that they “stole” Ø for that purpose. I put a backslash through my zeros instead, so it looks different. I usually pick a coding font with dotted zeros for the same reason.

I write plain text. I just happen to format it like markdown.

Programming is mostly understanding something abstract in your mind not rote memorization.

Even for a very simple program, focus on understanding what it does and how it does it, and why, step by step. Write things down when you learn something new.

Reading and understanding code, especially good code, will make you a good programmer. Just writing a ton of shit code will not. Trust me, I’ve done this for 3 decades and learn something new almost every day from reading other people’s code.

So, focus on understanding what it does, and you will be able to modify and build programs from scratch soon.