A great interviewer wouldn't be hung up on the "officially correct" way, but would instead expect the person to be aware of the different solutions and chat abo

A great interviewer wouldn't be hung up on the "officially correct" way, but would instead expect the person to be aware of the different solutions and chat about the trade-offs. A more likely case to the one you're describing would be someone suggesting implementing a search box with an O(N) search through an array (and offering no alternatives), and then being shown out the door.