Most homework assignments in this course involve writing, testing, and debugging a program. Although I may give one or two assignments to be done (and turned in) by teams of two, most assignments are to be done individually. If I see essentially identical programs turned in by three different people (not hard to spot, when one professor is in charge of all the students), I'll grade it once and divide the points among those students, so the best grade any of them can hope for is a 33%.
All work on the final exam must be entirely the work of the one person whose name is at the top of the page. If I have evidence that one student copied from another on an exam, both students will be penalized; see above.