Python/data_structures/linked_list/print_reverse.py

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from typing import List
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.append(f"{temp.data}")
temp = temp.next
return "->".join(string_rep)
def make_linked_list(elements_list: List):
"""Creates a Linked List from the elements of the given sequence
(list/tuple) and returns the head of the Linked List.
>>> make_linked_list([])
Traceback (most recent call last):
...
Exception: The Elements List is empty
>>> make_linked_list([7])
7
>>> make_linked_list(['abc'])
abc
>>> make_linked_list([7, 25])
7->25
"""
if not elements_list:
raise Exception("The Elements List is empty")
current = head = Node(elements_list[0])
for i in range(1, len(elements_list)):
current.next = Node(elements_list[i])
current = current.next
return head
def print_reverse(head_node: Node) -> None:
"""Prints the elements of the given Linked List in reverse order
>>> print_reverse([])
>>> linked_list = make_linked_list([69, 88, 73])
>>> print_reverse(linked_list)
73
88
69
"""
if head_node is not None and isinstance(head_node, Node):
print_reverse(head_node.next)
print(head_node.data)
def main():
from doctest import testmod
testmod()
linked_list = make_linked_list([14, 52, 14, 12, 43])
print("Linked List:")
print(linked_list)
print("Elements in Reverse:")
print_reverse(linked_list)
if __name__ == "__main__":
main()