Write a non-recursive traversal of a Binary Search Tree using constant space and O(n) run time
This is not homework, this is an interview question. The catch here is that the algorithm should be constant space. I'm pretty clueless on how to do this without a stack, I'd post what I've written using a stack, but it's not relevant anyway. Here's what I've tried: I attempted to do a pre-order traversal and I got to the left-most node, but I'm stuck there. I don't know how to "recurse" back up without a stack/parent pointer. Any help would be appreciated. (I'm tagging it as Java since that's what I'm comfortable using, but it's pretty language agnostic as is apparent.) iluxa I didn't think