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Code Single linked list

Reverse the linked list by words in python

Python program for Reverse the linked list by words. Here problem description and other solutions.

#  Python 3 program for
#  Reverse each word in a linked list node

#  Linked list node
class LinkNode :
	def __init__(self, data) :
		self.data = data
		self.next = None
	

class SingleLL :
	def __init__(self) :
		self.head = None
	
	def addNode(self, data) :
		node = LinkNode(data)
		node.next = self.head
		#  New first node
		self.head = node
	
	#  Display linked list element
	def display(self) :
		if (self.head == None) :
			return
		
		temp = self.head
		#  iterating linked list elements
		while (temp != None) :
			if (temp.data == ' ') :
				print(end = " ' '")
			else :
				print("", temp.data, end = "")
			
			print(end = " →")
			#  Visit to next node
			temp = temp.next
		
		print(" NULL")
	
	#  Reverse a single linked list
	def reverse(self) :
		if (self.head == None) :
			print("Empty linked list")
		else :
			back = None
			temp = self.head
			while (temp != None) :
				#  New head node
				self.head = temp
				#  Visit to next node
				temp = temp.next
				#  Connect with previous node
				self.head.next = back
				#  Get current node
				back = self.head
			
		
	
	#  Reversing words in linked list
	def reverseWord(self) :
		if (self.head == None) :
			print("\n Empty linked list")
			return
		
		#  Define some auxiliary variables
		temp = self.head
		start = None
		auxiliary = None
		separator = None
		hold = None
		self.head = None
		#  iterating linked list elements
		while (temp != None) :
			if (temp.data == ' ') :
				hold = temp
				#  Visit to next node
				temp = temp.next
				#  collect space ' '
				hold.next = separator
				separator = hold
				if (auxiliary != None) :
					auxiliary.next = None
				
				if (self.head == None) :
					self.head = start
				elif (start != None and auxiliary != None) :
					#  When more than one word exists
					hold = separator
					separator = hold.next
					auxiliary.next = hold
					hold.next = self.head
					self.head = start
				
				start = None
				auxiliary = None
			else :
				if (start == None) :
					start = temp
				
				auxiliary = temp
				#  Visit to next node
				temp = temp.next
			
		
		#  When no word exists
		#  Or Manage last word
		if (separator != None) :
			hold = separator
			#  When more than two space exist
			while (hold.next != None) :
				hold = hold.next
			
			hold.next = self.head
			self.head = separator
		
		if (auxiliary != None and start != None) :
			auxiliary.next = self.head
			self.head = start
		
		self.reverse()
	

def main() :
	sll = SingleLL()
	#   Constructed linked list
	sll.addNode('e')
	sll.addNode('d')
	sll.addNode('o')
	sll.addNode('C')
	sll.addNode(' ')
	sll.addNode('d')
	sll.addNode('o')
	sll.addNode('o')
	sll.addNode('G')
	sll.addNode(' ')
	sll.addNode('s')
	sll.addNode('I')
	sll.addNode(' ')
	sll.addNode('s')
	sll.addNode('i')
	sll.addNode('h')
	sll.addNode('T')
	#  T → h → i → s → ' ' → I → s → ' ' → 
	#  G → o → o → d → ' ' → C → o → d → e → NULL
	sll.display()
	sll.reverseWord()
	#  s → i → h → T → ' ' → s → I → ' ' → d → o → 
	#  o → G → ' ' → e → d → o → C → NULL
	sll.display()

if __name__ == "__main__": main()

Output

 T → h → i → s → ' ' → I → s → ' ' → G → o → o → d → ' ' → C → o → d → e → NULL
 s → i → h → T → ' ' → s → I → ' ' → d → o → o → G → ' ' → e → d → o → C → NULL

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