When answering negative sentences, remember to be consistent, that is, use affirmative auxiliary verbs after yes and negative auxiliary verbs after no. At this time, it means: no, it does not mean: yes. For example:

You are not a student. You are not a student.

If you are really not a student, the answer is: no, me? I didn't. No I don't. Followed by negation, and there is no agreement.

If you are a student, the answer is: Yes, I am. No, I am. After that, use affirmative, and are consistent.

So it's easy to say yes, it is. No, it's simple.