Introduction - If you have any usage issues, please Google them yourself
A set F that consists of a k independent vertex to a tree T is required to minimize the value of the cost (F) = min w (x) *d (x, U). Similar to the K median problem of the directed tree, it transforms the directed tree into an equivalent two branch tree, and sets the subtree T (x) of T with vertex x as its root, whose left and right son vertices are y and Z, respectively.