from collections import defaultdict

class Graph:

def __init__(self):

self.graph = defaultdict(list)

def addEdge(self, u, v):

self.graph[u].append(v)

def DFSUtil(self, v, visited):

visited[v] = True

print(v, end = ' ')

for i in self.graph[v]:

if visited[i] == False:

self.DFSUtil(i, visited)

def DFS(self, v):

visited = [False] * (max(self.graph)+1)

self.DFSUtil(v, visited)

# Create a graph given

g = Graph()

g.addEdge(0, 1)

g.addEdge(0, 2)

g.addEdge(1, 2)

g.addEdge(2, 0)

g.addEdge(2, 3)

g.addEdge(3, 3)

print("Following is DFS from (starting from vertex 2)")

g.DFS(2)