I used to do something like too, I remember putting my legs on water just because I wanted to stay awake but I never try staying hungry because I want to continue staying awake, and it's not even good to stay awake that much in the night because it might affect your day and your examsas well.

Who wouldn't laugh at such a thing, your fellow students wouldn't believe you, but they will think you do not know what to write in the answer booklet.