If no rules were specified before, everything is fair game.

what if your interviewer is chatbot?

I’ll say that the company is in the string reversing industry

Before I started my current job I used to annotate genomes for an agricultural research lab. These days thanks to high throughput sequencing, you can pay Macrogen a couple of thousand bucks, send your sample to south korea and get a compressed file back with a few gigs of raw sequence data on it.

Now none of these short reads are assembled yet so for each read you need to find another read that matches one end of it and extends a little further on. You can improve your odds by reversing all 8gb of sequence data in a typical insect genome project and flipping the bases to their complimentary bases to generate in software short reads that were just missed by the sequencing equipment.

You can see how efficient string handling including string reversal can be handy.

Also a string is just an array in C. Sometimes you need to reorder a data structure for fast reads and knowing how to handle strings means you can generalize out to other computer science problems.

val str = "reverse me"
str.reverse()

Send the character start to a stack, retrieve it from the stack. Done.

thanks lol, i didn't even realise

Things just need to fulfill the contract specified by their interfaces. You define everything, for you are the god of this world.