TL;DR
- no exceptions
- no recursion
- no malloc()/free() in the inner-loop
replies(9):
> no recursion
Does this actually mean no recursion or does it just mean to limit stack use? Because processing a tree, for example, is recursive even if you use an array, for example, instead of the stack to keep track of your progress. The real trick is limiting memory consumption, which requires limiting input size.