[leetcrew]

> How come this isn't possible in the US?

depends on the course, major, and school. in my CS major you could pretty easily get away with not purchasing the "required" textbook for most classes unless they assigned problems directly out of the book. even then, professors would often distribute PDF scans of the relevant problem pages. everything you actually needed to know for the exam would almost always be included in the monstrous PowerPoint lectures, so you could just study these if you didn't need extra help understanding the material.