pull/615/head
Vinay 2024-05-26 14:22:13 +05:30
rodzic 4a0576633f
commit b2264d4e6f
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@ -25,10 +25,12 @@ Let's code something
The smallest Unit: Node
```python
class Node:
def __init__(self, data):
self.data = data # Assigns the given data to the node
self.next = None # Initialize the next attribute to null
```
Now, we will see the types of linked list.
@ -44,20 +46,24 @@ There are mainly four types of linked list,
Simply think it is a chain of nodes in which each node remember(contains) the addresses of it next node.
### Creating a linked list class
```python
class LinkedList:
def __init__(self):
self.head = None # Initialize head as None
```
### Inserting a new node at the beginning of a linked list
```python
def insertAtBeginning(self, new_data):
new_node = Node(new_data) # Create a new node
new_node.next = self.head # Next for new node becomes the current head
self.head = new_node # Head now points to the new node
```
### Inserting a new node at the end of a linked list
```python
def insertAtEnd(self, new_data):
new_node = Node(new_data) # Create a new node
if self.head is None:
@ -67,9 +73,10 @@ Simply think it is a chain of nodes in which each node remember(contains) the ad
while last.next: # Otherwise, traverse the list to find the last node
last = last.next
last.next = new_node # Make the new node the next node of the last node
```
### Inserting a new node at the middle of a linked list
```python
def insertAtPosition(self, data, position):
new_node = Node(data)
if position <= 0: #check if position is valid or not
@ -89,21 +96,23 @@ Simply think it is a chain of nodes in which each node remember(contains) the ad
return
new_node.next = current_node.next #connect the intermediate node
current_node.next = new_node
```
### Printing the Linked list
```python
def printList(self):
temp = self.head # Start from the head of the list
while temp:
print(temp.data,end=' ') # Print the data in the current node
temp = temp.next # Move to the next node
print() # Ensures the output is followed by a new line
```
Lets complete the code and create a linked list.
Connect all the code.
```python
if __name__ == '__main__':
llist = LinkedList()
@ -121,7 +130,7 @@ Connect all the code.
llist.insertAtPosition(9,4) ## 1 2 3 <9> 4 10 7
# Print the list
llist.printList()
```
## output:
1 2 3 9 4 10 7
@ -129,14 +138,15 @@ Connect all the code.
### Deleting a node from the beginning of a linked list
check the list is empty otherwise shift the head to next node.
```python
def deleteFromBeginning(self):
if self.head is None:
return "The list is empty" # If the list is empty, return this string
self.head = self.head.next # Otherwise, remove the head by making the next node the new head
```
### Deleting a node from the end of a linked list
```python
def deleteFromEnd(self):
if self.head is None:
return "The list is empty"
@ -147,6 +157,7 @@ check the list is empty otherwise shift the head to next node.
while temp.next.next: # Otherwise, go to the second-last node
temp = temp.next
temp.next = None # Remove the last node by setting the next pointer of the second-last node to None
```
### Search in a linked list