DS Intro.png
1.Node Class.png
2. Linked List Class.png
3. Insert at Beginning.png
4. Insert at End.png
5. Insert after Node .png
6. Delete at Beginning.png
7. Delete at End.png
8. Delete Node .png
9. Print List .png
Example.png
PYTHON CODE
class Node:
def __init__(self,data):
self.data = data
self.next = None #Initially, each node points to None
class LinkedList:
def __init__(self):
self.head = None #The head points to the first node (or None if empty)
def insert_at_beginning(self,data):
new_node = Node(data)
new_node.next = self.head # The new node's next points to the old head
self.head = new_node # Update the head to the new node
def insert_at_end(self,data):
new_node = Node(data)
if self.head is None:
self.head = new_node
return
last_node = self.head
while last_node.next:
last_node = last_node.next
last_node.next = new_node
def insert_after_node(self,prev_node,data):
if prev_node is None:
print("The given previous node cannot be None")
return
new_node = Node(data)
new_node.next = prev_node.next # Update the head to the new node
prev_node.next = new_node # Connect the previous node to the new node
def delete_at_beginning(self):
if self.head is None:
return
self.head = self.head.next # Move the head to the next node, effectively deleting the first
def delete_at_end(self):
if self.head is None:
return
if self.head.next is None:
self.head = None
return
last_node = self.head
while last_node.next.next:
last_node = last_node.next
last_node.next =None
def delete_node(self,key):
temp = self.head
prev = None
if temp is not None and temp.data == key:
self.head = temp.next # Update the head if the key is at the beginning
temp = None
return
while temp is not None and temp.data != key:
prev = temp
temp = temp.next
if temp is None:
return # Key not found
prev.next = temp.next # Bypass the node to be deleted
def print_list(self):
temp = self.head
while temp:
print(temp.data,end= ' ')
temp = temp.next
print( )
llist = LinkedList()
llist.insert_at_beginning(15)
llist.insert_at_beginning(10)
llist.insert_at_beginning(5)
llist.insert_at_end(25)
llist.insert_at_end(30)
llist.insert_at_end(35)
llist.insert_after_node(llist.head.next.next,20)
llist.insert_after_node(llist.head.next.next.next,22)
llist.delete_at_beginning()
llist.delete_at_end()
llist.delete_node(22)
llist.print_list()
