Slightly off topic, but a candidate applying for a general programming position who claims knowledge of C++ in their CV is presenting an absolute gift for interviewers: because, if they actually do know their C++, then they are likely to be a strong candidate overall; conversely, if they are bullsh1tting you it is very easy to find this out quickly.
True story: once interviewed a guy who claimed to know C++; set him a challenge that he couldn't answer, simplified it a bit, still couldn't answer, we iterated down until I discovered he didn't even know how to declare an int variable. Turns out he had been a tester on a system written in C++ ...
I'm a C# developer and I've been strongly considering learning C++ in detail because I feel like it would make me a better programmer in general. However getting started with such a complex language seems daunting. Anyone know where one should start? C++11? C++14? Something even older?
I very much agree that it helps you understand the "programming stack" much more intimately. If that's what you are after, you'll also have the parts that are relevant to you covered relatively quickly (compared to fully "knowing" C++ which would probably take at least a decade).
I also agree with the other reply that the strongest learning experience is basically in the chronology of the language development. It takes running into a case where they are the best solution to really grasp "why include guards?", "why templates?", "why smart pointers?", "why iterators?" and so on, and you also gain a lot of appreciation for what compilers in other languages do for you behind the scenes.
I also highly recommend https://godbolt.org/, which allows you to see what machine code is produced in the end. Seeing all the template magic getting distilled to clean asm is quite amazing.
The way that I learned C++ was starting from how the language was developed. With functions, arrays, basic variables. Then moving onto classes and polymorphism. Then with C++11 and C++14 newer features.
True story: once interviewed a guy who claimed to know C++; set him a challenge that he couldn't answer, simplified it a bit, still couldn't answer, we iterated down until I discovered he didn't even know how to declare an int variable. Turns out he had been a tester on a system written in C++ ...