interactive-coding-challenges/linked_lists/linked_list/linked_list.py
Donne Martin 5977fc994d Update linked list challenge (#124)
Remove extraneous check within the find method.  Clean up delete method.
2016-11-27 08:43:48 -05:00

98 lines
2.5 KiB
Python

class Node(object):
def __init__(self, data, next=None):
self.next = next
self.data = data
def __str__(self):
return self.data
class LinkedList(object):
def __init__(self, head=None):
self.head = head
def __len__(self):
curr = self.head
counter = 0
while curr is not None:
counter += 1
curr = curr.next
return counter
def insert_to_front(self, data):
if data is None:
return None
node = Node(data, self.head)
self.head = node
return node
def append(self, data):
if data is None:
return None
node = Node(data)
if self.head is None:
self.head = Node(data)
return node
curr_node = self.head
while curr_node.next is not None:
curr_node = curr_node.next
curr_node.next = node
return node
def find(self, data):
if data is None:
return None
curr_node = self.head
while curr_node is not None:
if curr_node.data == data:
return curr_node
curr_node = curr_node.next
return None
def delete(self, data):
if data is None:
return
if self.head is None:
return
if self.head.data == data:
self.head = None
return
prev_node = self.head
curr_node = self.head.next
while curr_node is not None:
if curr_node.data == data:
prev_node.next = curr_node.next
return
prev_node = curr_node
curr_node = curr_node.next
def delete_alt(self, data):
if data is None:
return
if self.head is None:
return
curr_node = self.head
if curr_node.data == data:
curr_node = curr_node.next
return
while curr_node.next is not None:
if curr_node.next.data == data:
curr_node.next = curr_node.next.next
return
curr_node = curr_node.next
def print_list(self):
curr_node = self.head
while curr_node is not None:
print(curr_node.data)
curr_node = curr_node.next
def get_all_data(self):
data = []
curr_node = self.head
while curr_node is not None:
data.append(curr_node.data)
curr_node = curr_node.next
return data