Same story for sophomore, same story for junior year, I finally took it senior year because they wouldn't get another chance even though it still doesn't fit in the workload ha ha.

大二，大三都是如此，最后我到大四才来上这门课,因为即使学业再忙,再不选就没有机会了，哈哈。

哈佛公开课 - 计算机科学课程节选