Prove a center of a tree (or if not much harder, of any graph) lies on the longest path.
(I encountered this when I was reading an alternative proof for the property :"a tree has at most two centers")
Prove a center of a tree (or if not much harder, of any graph) lies on the longest path.
(I encountered this when I was reading an alternative proof for the property :"a tree has at most two centers")