w3resource

Python Linked List: Delete the first item from a singly linked list

Python Linked List: Exercise-6 with Solution

Write a Python program to delete the first item from a singly linked list.

Sample Solution:

Python Code:

class Node:
    # Singly linked node
    def __init__(self, data=None):
        self.data = data
        self.next = None
class singly_linked_list:
    def __init__(self):
        # Createe an empty list
        self.tail = None
        self.head = None
        self.count = 0

    def append_item(self, data):
        #Append items on the list
        node = Node(data)
        if self.head:
            self.head.next = node
            self.head = node
        else:
            self.tail = node
            self.head = node
        self.count += 1
    
    def delete_item(self, data):
        # Delete an item from the list
        current = self.tail
        prev = self.tail
        while current:
            if current.data == data:
                if current == self.tail:
                    self.tail = current.next
                else:
                    prev.next = current.next
                self.count -= 1
                return
            prev = current
            current = current.next
    def iterate_item(self):
        # Iterate the list.
        current_item = self.tail
        while current_item:
            val = current_item.data
            current_item = current_item.next
            yield val

items = singly_linked_list()
items.append_item('PHP')
items.append_item('Python')
items.append_item('C#')
items.append_item('C++')
items.append_item('Java')

print("Original list:")
for val in items.iterate_item():
    print(val)

print("\nAfter removing the first item from the list:")
items.delete_item('PHP')
for val in items.iterate_item():
    print(val)

Sample Output:

Original list:
PHP
Python
C#
C++
Java

After removing the first item from the list:
Python
C#
C++
Java

Flowchart:

Flowchart: Delete the first item from a singly linked list.

Python Code Editor:

Contribute your code and comments through Disqus.

Previous: Write a Python program to set a new value of an item in a singly linked list using index value.
Next: Write a Python program to delete the last item from a singly linked list.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.



Become a Patron!

Follow us on Facebook and Twitter for latest update.

It will be nice if you may share this link in any developer community or anywhere else, from where other developers may find this content. Thanks.

https://198.211.115.131/python-exercises/data-structures-and-algorithms/python-linked-list-exercise-6.php