DEV Community

C++ Interview Questions for Beginners: Most Asked Topics – Part 1

Rathod Ketan on August 06, 2024

C++ is a foundational programming language that many software developers encounter early in their careers. Understanding its core concepts is cruci...

Read full post

Paul J. Lucas • Aug 6

These questions are far too easy. No real-world interviewer would ask them. If a candidate doesn't know this stuff and s/he knows s/he doesn't know this stuff, s/he shouldn't be applying for a C++ job in the first place.

A real-world interviewer would ask you to implement something like an exception-safe string copy. In order to implement that, you have to use things like const and references anyway, so there's no point in asking trivial questions.

Rathod Ketan • Aug 9

Could you please share some of good questions? that would good for me. I am targeting Indian subordinate so there are people who doing there college/high school and do exam preparation with keyword like interview questions. logic behind that they think in exam they get questions related to interview.

Paul J. Lucas • Aug 9 • Edited

One of my standard questions is, given:

class C {
public:
    // ...
    C& operator=( C const &other );
    // ...
private:
    T *_p;
    // ...
};

implement operator=() such that it deletes the T object pointed to by this->_p and makes this->_p point to a copy of the T object pointed to by other->_p — does a “deep copy.”

(The type T doesn’t matter, but assume it’s an object of some other class—but do not assume anything else about T.)

After they implement it, ask them if their implementation is thread-safe and why or why not. If not, ask them to make it thread-safe.

"Easier" but better questions include:

What problem do enum classes solve?
What problem does adding explicit to a constructor solve?
When should you add explicit to a constructor?
When should you not add explicit to a constructor?
What problem do rvalue references solve?
In a multithreaded program, if you have a simple bool flag that needs to be shared among threads, is it OK just to use the bool as-is, or do you need something else to make the program thread-safe? Why or why not? If something else is needed, what is that something else?

Rathod Ketan • Aug 11

Magnificent indeed. @pauljlucas since I am creating list or article so i will use this content for my future post with advanced level tag. could you please share some beginner level questions.

Paul J. Lucas • Aug 11

Those are beginner-level questions. To me, a "beginner" is someone who knows the entire C++ language, but lacks experience.

Rathod Ketan • Aug 12 • Edited

Yes your definition is correct. however in my opinion cover basic details called "beginner". are you welling to guest post on my site ? regarding c++?

Paul J. Lucas • Aug 12

A "beginner" by your definition doesn't know enough to be able to fill a C++ role. They would never interview for such a role. So making up interview questions for them is a complete fiction.

I know nothing about your site.

Rathod Ketan • Aug 13

this is my site interviewspreparation.com based on my experience and asking every new person about they experience in technical round of interview I write post to cover there experience.

Your are correct. since I am creating a sequence of post regarding "beginner" i will cover these questions. beside you can check my site.

Paul J. Lucas • Aug 13

I'm not about to review your entire site.

That said, I think you may have prompted me to get around to writing an article about the C++ questions I've asked candidates (with answers). If/when I do that, I'd grant you permission to post the same article to your site provided that:

You give proper credit to me by name.
You do not modify the content of my article in any way.
You preserve all formatting as-is.
You link back to my article via a "This was originally published to dev.to" link.