I still remember my B-tree implementation in college. The professor wanted us to run it against his data. I quickly commented up my debug prints which introduce

I still remember my B-tree implementation in college. The professor wanted us to run it against his data. I quickly commented up my debug prints which introduced a bug with an "if" statement and failed for some of his test cases but I got most of the credit. Later I found the cause of the bug and got pissed off for such a silly mistake.