Question

Python 3:

Python 3:

Write a LinkedList class that has recursive implementations of the add, display, remove methods. You may use default arguments and/or helper functions.

class Node:
    """
    Represents a node in a linked list
    """
    def __init__(self, data):
        self.data = data
        self.next = None

class LinkedList:
    """
    A linked list implementation of the List ADT
    """
    def __init__(self):
        self.head = None

    def add(self, val):
        """
        Adds a node containing val to the linked list
        """
        if self.head is None:  # If the list is empty
            self.head = Node(val)
        else:
            current = self.head
            while current.next is not None:
                current = current.next
            current.next = Node(val)

    def display(self):
        """
        Prints out the values in the linked list
        """
        current = self.head
        while current is not None:
            print(current.data, end=" ")
            current = current.next
        print()

    def remove(self, val):
        """
        Removes the node containing val from the linked list
        """
        if self.head is None:  # If the list is empty
            return

        if self.head.data == val:  # If the node to remove is the head
            self.head = self.head.next
        else:
            current = self.head
            while current is not None and current.data != val:
                previous = current
                current = current.next
            if current is not None:  # If we found the value in the list
                previous.next = current.next

Answer 1

Solution:

class Node:
def __init__(self,data):
self.data=data
self.next=None

class LinkedList:#class definition
def __init__(self):
self.head=None

def add(self,head,val): #add method that adds elements using recursion
if(head==None):
return Node(val)

else:
head.next=self.add(head.next,val)
return head

def display(self,head):#prints elements in list using recursion
if(head==None):
return

print(head.data,end=" ")
self.display(head.next)

def remove(self,head,val):#remove elements from list using recursion
if(head==None):
return

if(head.data==val):
result=head.next
return result

head.next=self.remove(head.next,val)
return head

#Driver test code
head=None
o=LinkedList()
head=o.add(head,5)
head=o.add(head,6)

head=o.add(head,7)
head=o.add(head,8)

o.display(head)
print()
head=o.remove(head,6)
o.display(head)

Screenshots:

The Screenshots are attached below for reference.
Please follow them for proper indentation.
The methods are implemented using recursion.