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4e13755023
Rewrite the tree serialization and deserialization methods. Add applications of array and linked list.
39 lines
981 B
Python
39 lines
981 B
Python
"""
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File: list_node.py
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Created Time: 2021-12-11
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Author: Krahets (krahets@163.com)
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"""
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class ListNode:
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"""Definition for a singly-linked list node"""
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def __init__(self, val: int):
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self.val: int = val # 节点值
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self.next: ListNode | None = None # 后继节点引用
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def list_to_linked_list(arr: list[int]) -> ListNode | None:
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"""Generate a linked list with a list"""
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dum = head = ListNode(0)
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for a in arr:
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node = ListNode(a)
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head.next = node
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head = head.next
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return dum.next
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def linked_list_to_list(head: ListNode | None) -> list[int]:
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"""Serialize a linked list into an array"""
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arr: list[int] = []
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while head:
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arr.append(head.val)
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head = head.next
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return arr
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def get_list_node(head: ListNode | None, val: int) -> ListNode | None:
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"""Get a list node with specific value from a linked list"""
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while head and head.val != val:
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head = head.next
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return head
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