class Node:
    def __init__(self,value):
        self.data=value
        self.next=None
 
class Linkedlist:
    def __init__(self):
        self.head=None
        self.node=0
 
    def reverse(self):
        curr=self.head
        prevNod=None
 
        while curr != None:
            nextNod = curr.next
            curr.next=prevNod    
            prevNod=curr          
            curr=nextNod   
 
        self.head=prevNod
 
    def insert_head(self,value):
        new_node=Node(value)
        new_node.next=self.head
        self.head=new_node
        self.node=self.node+1
 
L = Linkedlist()
L.insert_head(4)
L.insert_head(3)
L.insert_head(2)
L.insert_head(1)
L.reverse()
print(L)

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NDU=

45