给定一棵有向树Ｔ，树Ｔ中每个顶点u都有一个权w[u]，树的每条边[u,v]也都有一个非负边长d[u,v]。有向树Ｔ的每个顶点u可以看做客户，其服务需求量为w[u]。每条边[u,v]的边长d[u,v]可以看做是运输费用。如果在顶点u处未设置服务机构，则将顶点u处的服务需求沿有向树的边（u,v]转移到顶点v处服务机构，则需付出的服务转移费用为w[u]*d[u,v]。树根处已设置了服务机构，现在要在树Ｔ中增设k处服务机构，使得整棵树Ｔ的服务转移费用最小。该算法对于给定的有向树Ｔ，计算在树Ｔ中增设k处服务机构的最小服务转移费用。

-Given to have a tree T, the tree T for each vertex u has a right to w [u], each tree edge [u, v] also has a non-negative edge length d [u, v]. Tree T has to each vertex u can be seen as customers, demand for their services w [u]. Each edge [u, v] of side length d [u, v] can be seen as are transportation costs. If vertex u Department is not set service agencies will be vertex u Services Department needs to have trees along the edge [u, v] transferred to the vertex v Department service agencies, it would take to pay the service fee for the transfer of w [u]* d [u, v]. Shugen Services Department has set up institutions, now in the tree T and a new k Department service agencies, making整棵Transfer Service tree T of minimum cost. The algorithm for a given directed tree T, calculated in the tree T and a new k services agencies transfer the cost of the smallest services.