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* Retranslate the complete English edition from Simplified Chinese * Polish three English explanations after reader-focused review
52 lines
1.5 KiB
Python
52 lines
1.5 KiB
Python
"""
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File: hashing_search.py
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Created Time: 2022-11-26
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Author: timi (xisunyy@163.com)
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"""
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import sys
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from pathlib import Path
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sys.path.append(str(Path(__file__).parent.parent))
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from modules import ListNode, list_to_linked_list
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def hashing_search_array(hmap: dict[int, int], target: int) -> int:
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"""Hash-based search (array)"""
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# Hash table key: target element; value: index
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# Return -1 if the hash table does not contain this key
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return hmap.get(target, -1)
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def hashing_search_linkedlist(
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hmap: dict[int, ListNode], target: int
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) -> ListNode | None:
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"""Hash-based search (linked list)"""
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# Hash table key: target element; value: node object
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# Return None if the hash table does not contain this key
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return hmap.get(target, None)
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"""Driver code"""
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if __name__ == "__main__":
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target = 3
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# Hash-based search (array)
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nums = [1, 5, 3, 2, 4, 7, 5, 9, 10, 8]
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# Initialize the hash table
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map0 = dict[int, int]()
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for i in range(len(nums)):
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map0[nums[i]] = i # key: element; value: index
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index: int = hashing_search_array(map0, target)
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print("Index of target element 3 =", index)
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# Hash-based search (linked list)
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head: ListNode = list_to_linked_list(nums)
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# Initialize the hash table
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map1 = dict[int, ListNode]()
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while head:
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map1[head.val] = head # key: node value; value: node
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head = head.next
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node: ListNode = hashing_search_linkedlist(map1, target)
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print("The node object corresponding to target value 3 is", node)
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