I am a new software developer that recently joined my company right after I finished my school. We use Microsoft Visual C++ for development. While at work, I found that many co-workers are very experienced in software development; they can code quickly to solve the problems. I feel the peer pressure and I want to improve my C++ coding skills and abilities urgently.
Though I have some coding tasks to do at work, I want to find more moderate-size problems to tackle at my spare-time. I don't want those problem sets in textbooks: they are too small and can usually be finished in 1 hour or so. I want to work on problems that can take days to work on, (e.g., multi-threaded programming, client-server communication, HTTP protocol exercises etc.).
Can anyone provide me a good source of such problem sets? Thank you very much!