| 摘要 |
A method used by a digital computer for generating a preferred processing order of the vertices in a directed graph. The method also detects any cycles that exist in the directed graph. The vertices of the directed graph represent components of a system and the arcs represent the interrelationships between components. Each arc is defined by a vertex pair consisting of a starting vertex and an ending vertex. Each vertex is either assigned or unassigned to a processing order and marked as either a leaf vertex or a non-leaf vertex. The method includes traversing the set of arcs of the directed graph and marking the starting vertex as a non-leaf vertex for each arc whose ending vertex is unassigned, traversing the set of vertices and for each vertex that is unassigned and a leaf vertex, assigning the vertex to the processing order; and for each vertex that is unassigned and a non-leaf vertex, marking it as a leaf vertex. If unassigned vertices remain in the set of vertices and no vertices were assigned to the processing order then a cycle exists in the directed graph. These steps are repeated as long as there are vertices in the set of vertices that are unassigned and no cycle has been detected.
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