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# Python implementation of  algorithm to print all SCCs 
  
from collections import defaultdict 
   
 
class Graph: 
   
    def __init__(self,vertices):
        self.V= vertices 
        self.graph = defaultdict(list) 
   
    
    def addEdge(self,u,v): 
        self.graph[u].append(v) 
   
    
    def DFSUtil(self,v,visited): 
         
        visited[v]= True
        print v, 
        
        for i in self.graph[v]: 
            if visited[i]==False: 
                self.DFSUtil(i,visited) 
  
  
    def fillOrder(self,v,visited, stack): 
        
        visited[v]= True
        
        for i in self.graph[v]: 
            if visited[i]==False: 
                self.fillOrder(i, visited, stack) 
        stack = stack.append(v) 
      
  
    
    def getTranspose(self): 
        g = Graph(self.V) 
  
    
        for i in self.graph: 
            for j in self.graph[i]: 
                g.addEdge(j,i) 
        return g 
  
   
    def printSCCs(self): 
          
        stack = [] 
       
        visited =[False]*(self.V) 
       
        
        for i in range(self.V): 
            if visited[i]==False: 
                self.fillOrder(i, visited, stack) 
  

        gr = self.getTranspose() 
          
        
        visited =[False]*(self.V) 
  
        while stack: 
            i = stack.pop() 
            if visited[i]==False: 
                gr.DFSUtil(i, visited) 
                print"" 
   

g = Graph(5) 
g.addEdge(1, 0) 
g.addEdge(0, 2) 
g.addEdge(2, 1) 
g.addEdge(0, 3) 
g.addEdge(3, 4) 
  
   
print ("Following are strongly connected components " +
                           "in given graph") 
g.printSCCs() 
#This code is contributed by Neelam Yadav