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can we code inorder,preorder and postorder in single code in python ? without using recursion

# Python3 program for the above approach

# Structure of the

# node of a binary tree

class Node:

	def __init__(self, x):

		self.data = x

		self.left = None

		self.right = None

# Function to print all nodes of a

# binary tree in Preorder, Postorder

# and Inorder using only one stack

def allTraversal(root):

	# Stores preorder traversal

	pre = []

	# Stores inorder traversal

	post = []

	# Stores postorder traversal

	inn = []

	# Stores the nodes and the order

	# in which they are currently visited

	s = []

	# Push root node of the tree

	# into the stack

	s.append([root, 1])

	# Traverse the stack while

	# the stack is not empty

	while (len(s) > 0):

		# Stores the top

		# element of the stack

		p = s[-1]

		#del s[-1]

		# If the status of top node

		# of the stack is 1

		if (p[1] == 1):

			# Update the status

			# of top node

			s[-1][1] += 1

			# Insert the current node

			# into preorder, pre[]

			pre.append(p[0].data)

			# If left child is not NULL

			if (p[0].left):

				# Insert the left subtree

				# with status code 1

				s.append([p[0].left, 1])

		# If the status of top node

		# of the stack is 2

		elif (p[1] == 2):

			# Update the status

			# of top node

			s[-1][1] += 1

			# Insert the current node

			# in inorder, in[]

			inn.append(p[0].data);

			# If right child is not NULL

			if (p[0].right):

				# Insert the right subtree into

				# the stack with status code 1

				s.append([p[0].right, 1])

		# If the status of top node

		# of the stack is 3

		else:

			# Push the current node

			# in post[]

			post.append(p[0].data);

			# Pop the top node

			del s[-1]

	print("Preorder Traversal: ",end=" ")

	for i in pre:

		print(i,end=" ")

	print()

	# Printing Inorder

	print("Inorder Traversal: ",end=" ")

	for i in inn:

		print(i,end=" ")

	print()

	# Printing Postorder

	print("Postorder Traversal: ",end=" ")

	for i in post:

		print(i,end=" ")

	print()

# Driver Code

if __name__ == '__main__':

	# Creating the root

	root = Node(1)

	root.left = Node(2)

	root.right = Node(3)

	root.left.left = Node(4)

	root.left.right = Node(5)

	root.right.left = Node(6)

	root.right.right = Node(7)

	# Function call

	allTraversal(root)

	# This code is contributed by mohit kumar 29.

Hope this code will help you.