DepthSearch.py

from collections import defaultdict


class Graph:

	# Constructor
	def __init__(self):

		self.graph = defaultdict(list)

	def addEdge(self, u, v):
		self.graph[u].append(v)

	# A function used by DFS
	def DFSUtil(self, v, visited):

		visited.add(v)
		print(v, end=' ')

	
		for neighbour in self.graph[v]:
			if neighbour not in visited:
				self.DFSUtil(neighbour, visited)

	
	def DFS(self, v):

		visited = set()

		self.DFSUtil(v, visited)

if __name__ == "__main__":
	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)")
	# Function call
	g.DFS(2)