Why is C++ knowledge beneficial? Will there be any use further in future?

Answer 1

C++ goes a bit deeper than Java and C#, and if you want some nice, clean and optimized code (without using assembly language), C++ is the way to go. It's been around for more than 30 years, I doubt it will die that soon.

Answer 2

C++ have better performance then Java and C#, so it Will be used for a long time yet. C# was influencied by C++, but never Will be so Great about optimization.