It is 2 or 3 years that I'm dealing with C++. I have heard that almost about 10 years hard work is needed to be a real C++ programmer, an expert. Apparently (judging by the time I have spent so far while I think I'm still a novice in C++), that saying is true. :(
Then, we should spend also few years for any other language for being an expert in them.
I know that if someone be adept in C++, they can learn C, C# and Java in a short time, because these languages are near to each other. But how short?
I looked at the page of Helios here on this website. He is adept in many programming languages while is younger than me. So how much time is needed that I be an expert in those many languages!?
And is it possible for someone to really be an expert in many programming languages?
Those 10+ years are not years of study, they are years of working experience, of having a successful career as a software engineer who is always willing to learn new things that make them better at their job. It's the same way for any non-academic programming language - C++, Java, C# included. Becoming an expert is a side-effect, it's not something you can actually achieve "in a short time". Why do you want it, anyway?
And yes, a C++ expert is expected to be familiar with multiple programming languages, frameworks, and technologies, both because real-life software is almost never homogeneous and because it's important to make informed choices. As for being a leading expert in multiple languages.. there aren't enough hours in a day.
Actually I don't want to learn another language in a short time. I just want to know how many years does it take to learn C# if I learnt C++ in four years hard study? How long for learning Java after C#, please?
I think its like learning English, German, Arabic, Chinese, etc. Each one you learn makes the next come easier.
I started on mainframes in the 70s with Fortran. Then basic and asm on PCs in the 80s. Next C, C++, Visual Basic in the 90s. Now I mostly do PowerBASIC and C/C++.