That has little to do with burning a CD. The particular problem you bring as an example is a small and completely optional problem that one would be faced compared to the entire task. And I could look up a solution in 15 minutes.
This whole downvote storm is because your OP was "CS students love dropping four letters: P, NP, O and N. Whenever I want to judge who was a bit too focused on the surface details of computer science, and too little on the real problems, I wait to see if those 4 letters come up in a sentence." and there is a crowd of people here whose work on real problems involves those four letters all the time & couldn't be done without extensive knowledge about them and discussing them endlessly.
Maybe they don't come up so often when writing cd burning programs or robotics (though I find the latter hard to believe since any planning algorithms should hit up against this quickly), but other people have their own real problems where it does. I'm trying hard not to be dismissive here, even though your original post reeked of dismissiveness.
You would have to be crazy smart to figure out P,NP, etc. in 15 minutes without pre-existing knowledge of it.