hello-algo/codes/python/modules/linked_list.py
Yudong Jin 8918ec9079
refactor: Follow the PEP 585 Typing standard (#439)
* Follow the PEP 585 Typing standard

* Update list.py
2023-03-23 18:51:56 +08:00

34 lines
1,001 B
Python

"""
File: linked_list.py
Created Time: 2021-12-11
Author: Krahets (krahets@163.com)
"""
class ListNode:
""" Definition for a singly-linked list node """
def __init__(self, val: int):
self.val: int = val # 结点值
self.next: ListNode | None = None # 后继结点引用
def list_to_linked_list(arr: list[int]) -> ListNode | None:
""" Generate a linked list with a list """
dum = head = ListNode(0)
for a in arr:
node = ListNode(a)
head.next = node
head = head.next
return dum.next
def linked_list_to_list(head: ListNode | None) -> list[int]:
""" Serialize a linked list into an array """
arr: list[int] = []
while head:
arr.append(head.val)
head = head.next
return arr
def get_list_node(head: ListNode | None, val: int) -> ListNode | None:
""" Get a list node with specific value from a linked list """
while head and head.val != val:
head = head.next
return head