59 lines
1.4 KiB
Python
59 lines
1.4 KiB
Python
# A simple Python program to create a singly linked list
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# Node class
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class Node:
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# Function to initialise the node object
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def __init__(self, data):
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self.data = data # Assign data
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self.next = None # Initialize next as null
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# Linked List class contains a Node object
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class LinkedList:
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# Function to initialize head
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def __init__(self):
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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 insertAtHead(self, new_data):
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# 1 & 2: Allocate the Node &
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# Put in the data
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new_node = Node(new_data)
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# 3. Make next of new Node as head
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new_node.next = self.head
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# 4. Move the head to point to new Node
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self.head = new_node
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def removeAtHead(self):
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temp = self.head
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# If head node itself holds the key to be deleted
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if (temp is not None):
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self.head = temp.next
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temp = None
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return
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else:
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return('underflow')
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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)
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temp = temp.next
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# Code execution starts here
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if __name__=='__main__':
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l=LinkedList()
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l.insertAtHead(1)
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l.insertAtHead('xyz')
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l.insertAtHead(1.1)
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l.removeAtHead()
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l.printList()
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