Exactly. An on-the-job developer who hand-rolls some tricky but well known algorithm from scratch is being foolish. It would be much more productive to see how their google-fu is.
Do they know which algorithm families to look up? Do they know which libraries in the given language will likely have the algorithms already available? That's what a real developer needs to know so why not interview for that.
Do they know which algorithm families to look up? Do they know which libraries in the given language will likely have the algorithms already available? That's what a real developer needs to know so why not interview for that.