Ask HN: Recommended Online C/C++ Courses for a Ruby Developer

Title says it all! I have years on Ruby/Sinatra/Rails with a bit of JavaScript, Python, SQL, etc mixed in building lots of web applications. Also a little bit of toying with Arduinos and electronics.

Can anyone recommend an amazing online C/C++ course that would be well suited for someone with 10+ years of Ruby/Rails/mostly web experience? I've seen a lot of options with a quick Google but I'm asking here because I feel that I'll find people that have that matching center of the venn diagram, being existing programmers that may have wanted to expand their skills.

If it matters, I'm gunning towards job listings, "in space" when this is over (assuming that industry still is hiring in a few months) and I'm already taking some physics and calc courses.

Recs are appreciated!