题目链接 Problem Description RXD has a tree T, with the size of n. Each edge has a cost. Define f(S) as the the cost of the minimal Steiner Tree of the set S on tree T. he wants to divide 2,3,4,5,6,-n into k parts S1,S2,S3,-Sk, where ⋃Si={2,3,-,n} and fo…