u/Hellkyte

Apologies in advance for any language I butcher here. I am trying to formalize a model and I no longer have a mathematician on staff so I'm hoping y'all could help

I need to describe a hierarchy in sets. For example, let's say I have a set of all continents C, and a set of all countries U.

Each country is assigned to one and only one continent.

How would I write this, and is there a name for this (I just guessed with the hierarchical set thing, but googling that doesn't seem to give what I'm looking for, and I don't trust the AI response on this question)

Thanks in advance, any help is appreciated

Ed: this seems to have to do with partitions