How is this different than the OP? You said that you're keen on a real world problem, except that BSTs can definitely be involved in a real world problem. If an

How is this different than the OP? You said that you're keen on a real world problem, except that BSTs can definitely be involved in a real world problem. If anything, this problem is more complicated than the one the OP presents. From afar, it sounds like a translation of your posts are "I'm not familiar with BST, that's unfair. I'd rather a real world problem like the one I'm familiar with". As someone who never works with addresses, while reading over your various descriptions of the sub-problems I think your familiarity with the problem is clouding your judgement on the "very easily" parts, at least as compared to the original BST problem space (i.e. "someone can figure out what's necessary in ~10 mins in a high pressure situation). Perhaps that's unfair of me but I don't see how your arbitrary problem which is fairly simple in the standard case but with a variety of interesting edge cases is any different than his problem of a similar description.