Comment by Afforess

I agree. I feel the overpowering urge, when asked this sort of basic interview question, to shout back "WHY?". What does inverting a binary tree have to do with software engineering, at all?

Google (and other interviewers) might as well be asking me to name the last 1000 digits of PI. The Kafkaesquen ability to recite how to do the task correctly reflects nothing about the candidate, except the strength of their memory.

It boggles the mind that the field of computer science does not have any standard way to detect the competency of a person. It is extremely discongruous for a company with as many smart people as Google to have such an absurd hiring policy.