[bjourne]

Suppose you are a teacher for a group of programming students. You ask them to implement a binary tree in C. The first student comes up with a verbatim copy of the code on Rosetta Code, the second with the same code with some variable names changed, and he third with indentation changed from tabs to spaces. Which of them were cheating?

[ibeale1]

I think this hypothetical might miss the point of the comment it's replying to. In my mind, cheating requires intention. Now, it would be hard for the student to disprove that any of these situations were not intentional but if for example the student studied Rosetta for the exam, it's very possible the student just memorized the code and didn't reference it during the test. Is that still cheating?

[bjourne]

Cheating does not require intent. That is, the university only has to prove that the student's work is not original to conclude that plagiarism and also cheating has occurred. Memorization is usually not prohibited in exams.