Auto as it is now has been in C++ since C++11, thats more than a decade ago...
If your argument was C then sure thats a C23 feature (well the type inference type of auto ) and is reasonably new.
This is much more a reflection on youe professor than the language. C++11 was a fundamental change to the language, anyone teaching or using C++ in 2025 should have an understanding of how to to program well in a 14 year old version of said language...
Decades ols books in C most certainly is even useful in modern C++23 because you need to interact with other libraries written in C89.
When a lot of modern CS concepts wwre first discovered and studied in the 70s, there's no point arguing that old books are useless. Honestly there may be sections of old books that are useless but in the whole they are still useful.
We're talking about learning C/C++ from scratch which makes no sense to do by using a decades old book because it wouldn't teach you any modern features. Also we're not talking about computer science.
Some people want to use them, they are useful in some contexts and they often already exist in some form elsewhere, but the majority of people often do not need them.
That said, when you learn a foreign language, you do not learn every word in the dictionary and every grammatical structure. The same is true for programming. You just don't need to have a more up to date book than one on C89 to begin learning C.
If your argument was C then sure thats a C23 feature (well the type inference type of auto ) and is reasonably new.
This is much more a reflection on youe professor than the language. C++11 was a fundamental change to the language, anyone teaching or using C++ in 2025 should have an understanding of how to to program well in a 14 year old version of said language...