求可达矩阵的Warshall算法

给出并证明了确定内部独立的递阶层次结构的矩阵方法。将系统用有向图描述，利用集合论中求关系问包的Ｗａｒｓｈａｌｌ算法实现了求可达矩阵。在决策因素很多且问题很复杂时，可以通过有向图的可达矩阵来确定系统的层次结构。

The Warshall Algorithm for Computing Reachability Matrix

The method of constructing hierarchical structure with inner independence isintroduced and proved.The system is described by directed graph. The reachability matrix ofdirected graph is computed by Warshall algorithm for computing transitive closure of relationshipin set theory.When decision-making problem is complex and there are many decision-makingfactors,hierarchical structure may be constructed by the reachability matrix of directed graph.