I am working on a project to compare dynamic pathfinding algorithms, and LPA* or more precisely D* Lite is one of the algorithms, I picked. The issue I have atm is after multiple obstacle additions and removal, especially when interconnected nodes become orphaned, and later rejoin the tree create cycles in the tree. I tried to follow the pseudocode and the sample code very closely, but no matter how many times I rewrite the class, I end up with this issue. In the end I decided to to explicit ancestry check every time the parent was changed. It seems to work decently, although at times it results in an unnatural looking tree. I was wondering if there was a well known omission from the pseudocode presented in the documentation that may be an easy fix for the issue. I can include code, although it's slightly on the lengthy side.