Hello codeforces

This is my AMA! You tell me something, and I will tell you if that thing enters the music box.

I swear to fucking god if you already know what enters it, and you spoil it, I will make it my life's duty to demolish you and your career.

First person that gets it, can DM me, but I won't give prizes because I am broke.

Good luck!

Francisc.