In Europe high school is when you get a generic education, and in college you choose your topic. So if you are a languages major you'll have no more math, if you're a STEM major you'll have no more history, if you're a philosophy major you might have logic and some history but no physics or linear algebra, and so on.

I studied computer science (M.Eng.) and I had to provide an English certification as a foreign language, but that was it. The only non-computer science, non-math, non-electronics courses were one semester of chemistry, one of economics and three of physics (which you could say is related to electronics though). So basically 15-20%.

Having to study more history or biology would have been a huge waste of time in a CS university, and I say that as someone who did more Latin and Greek than math and physics in high school.