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Python - Singly LinkedList That Allows Append, Prepend, Insert at Index, Pop First, Pop Last, Delete at Index, Delete Value, and View LinkedList

Singly LinkedList in Python that allows append, prepend, insert at index, delete first element, delete last element, delete from index, delete a value,  and view LinkedList operations
Run the code here: https://repl.it/@VinitKhandelwal/SinglyLinkedList
class SinglyLinkedList:

def __init__(self):
self.reset()
def reset(self):
self.length = 0
self.head = None
self.tail = None

def first_node(self, new_node):
self.head = new_node
self.tail = self.head
self.length += 1

def append_non_first(self, new_node):
self.tail.front_pointer = new_node
self.tail = new_node
self.length += 1

def prepend_non_first(self, new_node):
new_node.front_pointer = self.head
self.head = new_node
self.length += 1

def append(self, value):
new_node = Node(value)
if self.length == 0:
self.first_node(new_node)
else:
self.append_non_first(new_node)

def prepend(self, value):
new_node = Node(value)
if self.length == 0:
self.first_node(new_node)
else:
self.prepend_non_first(new_node)

def insert_at(self, index, value):
new_node = Node(value)
if self.length == 0:
self.first_node(new_node)
elif index > self.length+1:
print("Index not available. Appended at the end.")
self.append_non_first(new_node)
else:
temp = self.head
if index == 0:
self.prepend_non_first(new_node)
elif index == self.length+1:
append_non_first(new_node)
else:
for i in range(0, index):
prev_temp = temp
temp = temp.front_pointer
prev_temp.front_pointer = new_node
new_node.front_pointer = temp
self.length += 1

def pop_front_non_first(self):
self.head = self.head.front_pointer
self.head.back_pointer = None
self.length -= 1

def pop_last_non_first(self):
prev_temp = self.head
for i in range(1, self.length):
temp = prev_temp.front_pointer
prev_temp = temp
prev_temp.front_pointer = None
self.length -= 1

def popfirst(self):
if self.length < 2:
self.reset()
else:
self.pop_front_non_first()

def poplast(self):
if self.length < 2:
self.reset()
else:
self.pop_last_non_first()

def delete_at(self, index):
if self.length < 2:
self.reset()
elif index == 0:
self.pop_front_non_first()
elif index == self.length-1:
self.pop_last_non_first()
elif index < self.length and index > 0:
temp = self.head
for i in range(0, index):
prev_temp = temp
temp = prev_temp.front_pointer
prev_temp.front_pointer = temp.front_pointer
self.length -= 1

def delete(self, value):
if self.length < 2:
if self.head.value == value:
self.reset()
else:
if self.head.value == value:
self.pop_front_non_first()
if self.tail.value == value:
self.pop_last_non_first()
prev_temp = self.head
for i in range(1, self.length-1):
temp = prev_temp.front_pointer
if temp.value == value:
prev_temp.front_pointer = temp.front_pointer
self.length -= 1
prev_temp = temp
def view(self):
print("View")
temp = None
arr = []
for i in range(0, self.length):
if temp == None:
temp = self.head
else:
temp = temp.front_pointer
if temp is not None:
arr.append(temp.value)
print(arr)


class Node:
def __init__(self, value, back_pointer=None, front_pointer=None):
self.value = value
self.front_pointer = front_pointer

obj = SinglyLinkedList()
obj.view()
obj.prepend(10)
obj.view()
obj.append(1)
obj.view()
obj.append(10)
obj.view()
obj.prepend(2)
obj.view()
obj.insert_at(3, 7)
obj.view()
obj.prepend(3)
obj.view()
obj.prepend(10)
obj.view()
obj.prepend(4)
obj.view()
obj.prepend(10)
obj.view()
obj.delete(10)
obj.view()
obj.delete_at(2)
obj.view()
obj.popfirst()
obj.view()
obj.poplast()
obj.view()
OUTPUT
View
[]
View
[10]
View
[10, 1]
View
[10, 1, 10]
View
[2, 10, 1, 10]
View
[2, 10, 1, 7, 10]
View
[3, 2, 10, 1, 7, 10]
View
[10, 3, 2, 10, 1, 7, 10]
View
[4, 10, 3, 2, 10, 1, 7, 10]
View
[10, 4, 10, 3, 2, 10, 1, 7, 10]
View
[4, 3, 2, 1, 7]
View
[4, 3, 1, 7]
View
[3, 1, 7]
View
[3, 1]

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