Yes you are right that you normally wouldn't change the input vector. I wanted to keep it as simple as possible with this one, that's why I didn't make it constant. But I will change it :)

IMHO you should make the entry vector CONST... In a code lib you may not expect to change (sort) the vector input ??

You are right. It should be fixed now... Thank you for telling me!

Have you run the sample tests? They don't compile. That's the issue.

They would work if you used the statement using namespace std;...

but as a better practice, instead simply use the prefix std:: where needed.

And the same is the case for both the solution set-up as well as the sample tests fields.

I have removed unnecessary test cases and added random cases. I also changed the sample test and added the one for one task. Is that what you meant?

I have added random test cases, thanks for the feedback!

sample tests are set up incorrectly

no random tests