52 lines
1.1 KiB
Python
52 lines
1.1 KiB
Python
# reverse a given linkedlist
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class Node:
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# Constructor to initialize the node object
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def __init__(self, data=0, next=None):
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self.data = data
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self.next = next
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class LinkedList:
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# Constructor to initialize head
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def __init__(self) -> None:
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self.head = None
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# Function to insert a new node at the beginning
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def push(self, data):
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node = Node(data)
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node.next = self.head
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self.head = node
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# Function to print the list from beginning
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def printList(self):
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temp = self.head
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while temp:
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print(temp.data, end=" ")
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temp = temp.next
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# Function to reverse the list
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def reverse(self):
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dummy = None
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cur = self.head
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while cur:
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nextTemp = cur.next
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cur.next = dummy
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dummy = cur
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cur = nextTemp
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self.head = dummy
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if __name__ == '__main__':
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ll = LinkedList()
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ll.push(1)
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ll.push(2)
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ll.push(3)
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ll.push(4)
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ll.push(5)
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print("Before Reverse")
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ll.printList()
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ll.reverse() # reversing
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print("\nAfter Reversing")
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ll.printList()
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