mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-11-24 13:31:07 +00:00
4c37eb7d07
* Improved Singly Linked List Added String Representations of Nodes and Linked Lists Added support for indexing and changing of Node data using indices. * Added a few comments to Linked Lists * Reformatted to conform to PEP8 * Added from_sequence.py Convert a Python List to Linked List comprising of Nodes and return head. * Added print_reverse.py Recursive program to print the elements of a Linked List in reverse. * Change 'is not None' for more Pythonicness
56 lines
1.4 KiB
Python
56 lines
1.4 KiB
Python
# Program to print the elements of a linked list in reverse
|
|
|
|
class Node:
|
|
def __init__(self, data=None):
|
|
self.data = data
|
|
self.next = None
|
|
|
|
def __repr__(self):
|
|
"""Returns a visual representation of the node and all its following nodes."""
|
|
string_rep = ""
|
|
temp = self
|
|
while temp:
|
|
string_rep += f"<{temp.data}> ---> "
|
|
temp = temp.next
|
|
string_rep += "<END>"
|
|
return string_rep
|
|
|
|
|
|
|
|
def make_linked_list(elements_list):
|
|
"""Creates a Linked List from the elements of the given sequence
|
|
(list/tuple) and returns the head of the Linked List."""
|
|
|
|
# if elements_list is empty
|
|
if not elements_list:
|
|
raise Exception("The Elements List is empty")
|
|
|
|
# Set first element as Head
|
|
head = Node(elements_list[0])
|
|
current = head
|
|
# Loop through elements from position 1
|
|
for data in elements_list[1:]:
|
|
current.next = Node(data)
|
|
current = current.next
|
|
return head
|
|
|
|
def print_reverse(head_node):
|
|
"""Prints the elements of the given Linked List in reverse order"""
|
|
|
|
# If reached end of the List
|
|
if head_node is None:
|
|
return None
|
|
else:
|
|
# Recurse
|
|
print_reverse(head_node.next)
|
|
print(head_node.data)
|
|
|
|
|
|
|
|
list_data = [14,52,14,12,43]
|
|
linked_list = make_linked_list(list_data)
|
|
print("Linked List:")
|
|
print(linked_list)
|
|
print("Elements in Reverse:")
|
|
print_reverse(linked_list)
|