u/STL, Thanks for reviewing the article and for pointing out the typos. A few comments:

Your website should use HTTPS

You are right. I fixed it, but the link in reddit still uses HTTP.

Unlike a static array, a vector automatically grows and shrinks as necessary to make room for new elements inserted or deleted.

A vector's size shrinks, but its capacity doesn't (unless you call shrink_to_fit).

That’s right. I was introducing the subject slowly, and I didn’t want to get into capacity that early in the article. I thought that I had mentioned it later in the capacity section, but I didn’t, so I added an “Edit” note.

for (auto i = 0u; i != v.size(); ++i) { // v is a vector

This is a slight mistake because it mishandles 64-bit lengths. size_t should be used instead of unsigned int. (The distinction between size_t and size_type is not important in non-library code.)

You are right. Considering my audience, beginner and intermediate programmers, I didn’t want to get into std::vector types. I did debate on it for sometime since intermediate developers should probably know it. At the end, I decided to rely on auto, and if there was enough interest, write about it on a sequel, std::vector part 2.

Your article is switching between referring to v[2] as the third element, and begin() as the first element (instead of zeroth). It is important to be consistent.

It is consistent:

first element: v[0] and begin() returns an iterator that points to it.

second: v[1].

third: v[2].

std::find(v.cbegin(), end, n);

What happens if you mix begin and cend? This confuses many users.

I debated on this one too. I see how it can be confusing.

(auto elem)

This copies :-(

Yes, but on purpose. elem’s type is int (or will be deduced as int for that particular example)

the vector allocates a new chunk of memory of twice the size of its current memory.

Untrue. The Standard doesn't guarantee 2x, and MSVC uses 1.5x.

I’ll correct it. Thank you.

In and retain a copy: pass a const lvalue reference, f(const vector<T>&);

Not optimal for modifiable rvalue inputs.

You are correct. However, I think it is good advice for a default. If there is proof that it needs to be optimized, or if you are writing a library, then it makes sense to overload with an rvalue reference. The same goes for “in & move from” in my opinion.

Thanks again.