[cema]

Yes, it's basic. But many people who are not fresh out of college may have spent recent years solving a completely different set of programming tasks, and do not have it loaded in their brains.

When applicants prepare for an interview, they do not often know what kind of knowledge to load in their heads. For example, just a couple of weeks ago I was asked to figure out a simple bit-flipping scheme, and bit string manipulations are something that I have not thought about in many years. So it took me about 10 minutes for a problem that I would have done in less than a minute when I was spending time thinking about similar things and my mind was full with them.

Being prepared for a technical interview does not mean to have memorized a few solutions to a few problems, but it means to have played with them sufficiently to have the brain loaded with the material. This helps with intuition as well as specific technical skills.