It turns out, some CS professors prefers assignments submitted on paper, rather than on file. Quite possibly due to lack of ink, paper, printer, and/or computer in their office, just as expected from a CS professor.
However, code-on-paper has one great weakness: they cannot be compiled/executed by the computer directly. If one were to do that, one would need to do OCR, or one would have to type the whole thing back into a file. Considering the lack of ink/etc in the office, I would not expect them to have a good mean of OCR. And thus, I must conclude that there are some poor souls that have to type the whole source code, or that the code will never be really tested. Assuming the former, I decided to put my code-that-had-to-be-printed online too, so I can lessen the suffering of mankind. In case of latter, doing this probably doesn't hurt anyone, so it's fine.
To make sure no one else tries to submit my code and still look like one wasn't late, code shall be committed and pushed after the submission.
Source code in this repository is licensed under the MIT License; See LICENSE. That probably means it's technically fine to hand the code in as an assignment if you include the license file. But please consult your professor before doing so, or maybe do your homework yourself.