IDDFS.py

from collections import defaultdict

# list representation
class Graph:

	def __init__(self,vertices):
		self.V = vertices
		self.graph = defaultdict(list)

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

	def DLS(self,src,target,maxDepth):
		if src == target : return True

		if maxDepth <= 0 : return False

		for i in self.graph[src]:
				if(self.DLS(i,target,maxDepth-1)):
					return True
		return False

	def IDDFS(self,src, target, maxDepth):

		for i in range(maxDepth):
			if (self.DLS(src, target, i)):
				return True
		return False

# Create a graph given in the above diagram
g = Graph (7)
g.addEdge(0, 1)
g.addEdge(0, 2)
g.addEdge(1, 3)
g.addEdge(1, 4)
g.addEdge(2, 5)
g.addEdge(2, 6)

target = 6; maxDepth = 3; src = 0

if g.IDDFS(src, target, maxDepth) == True:
	print ("Target is reachable from source " +
		"within max depth")
else :
	print ("Target is NOT reachable from source " +
		"within max depth")