length_linkedlist.py

class Node: 
	# Function to initialise the node object 
	def __init__(self, data): 
		self.data = data # Assign data 
		self.next = None # Initialize next as null 


# Linked List class contains a Node object 
class LinkedList: 

	# Function to initialize head 
	def __init__(self): 
		self.head = None


	# This function is in LinkedList class. It inserts 
	# a new node at the beginning of Linked List. 
	def push(self, new_data): 

		# 1 & 2: Allocate the Node & 
		#	 Put in the data 
		new_node = Node(new_data) 

		# 3. Make next of new Node as head 
		new_node.next = self.head 

		# 4. Move the head to point to new Node 
		self.head = new_node 


	# This function counts number of nodes in Linked List 
	# iteratively, given 'node' as starting node. 
	def getCount(self): 
		temp = self.head # Initialise temp 
		count = 0 # Initialise count 

		# Loop while end of linked list is not reached 
		while (temp): 
			count += 1
			temp = temp.next
		return count 


# Code execution starts here 
if __name__=='__main__': 
	llist = LinkedList() 
	llist.push(1) 
	llist.push(3) 
	llist.push(1) 
	llist.push(2) 
	llist.push(1) 
	print ("Count of nodes is :",llist.getCount())