Python拓扑排序_惠州计算机Python软件开发

from collections import defaultdict 

class Graph:

      def __init__(self,vertices):

            self.graph = defaultdict(list)

            self.V = vertices

     def addEdge(self,u,v):

            self.graph[u].append(v)

     def topologicalSortUtil(self,v,visited,stack):

            visited[v] = True

            for i in self.graph[v]:

                 if visited[i] == False:

                      self.topologicalSortUtil(i,visited,stack)

           stack.insert(0,v)

     def topologicalSort(self):

           visited = [False]*self.V

           stack =[]

           for i in range(self.V):

                 if visited[i] == False:

                      self.topologicalSortUtil(i,visited,stack)

         print (stack)  

g= Graph(6) 

g.addEdge(5, 2); 

g.addEdge(5, 0); 

g.addEdge(4, 0); 

g.addEdge(4, 1); 

g.addEdge(2, 3); 

g.addEdge(3, 1);     

print ("拓扑排序结果：")

g.topologicalSort()