Right, and they don't want "most people" applying. That's the point. I could probably do it, but not blindfolded -- I'd have to work out (or look up) the deta

Right, and they don't want "most people" applying. That's the point. I could probably do it, but not blindfolded -- I'd have to work out (or look up) the details, because R/B-trees are the one data structure I learned in college that I have never once used. But I do know at least one person who can implement a R/B-tree in assembly off the top of his head. Coincidentally or not, he's at Google now.