We do an even easier question - "Pretend I'm the client and I want you to write a method - Given a List of strings, write a method to concatenate them together with a space in-between."
For starters, it's staggering how many people can't do it.
But also, it's a great question because it's simple enough that you don't have to be clever but you can get a feeling for all sorts of things. Do they ask questions? Any questions? What possible inputs might cause problems? What do they name their method? What tests do they write? (Project is set up already with an example test class ready to go.) Etc etc
For starters, it's staggering how many people can't do it.
But also, it's a great question because it's simple enough that you don't have to be clever but you can get a feeling for all sorts of things. Do they ask questions? Any questions? What possible inputs might cause problems? What do they name their method? What tests do they write? (Project is set up already with an example test class ready to go.) Etc etc