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* Retranslate the complete English edition from Simplified Chinese * Polish three English explanations after reader-focused review
118 lines
3.1 KiB
Python
118 lines
3.1 KiB
Python
"""
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File: array_hash_map.py
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Created Time: 2022-12-14
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Author: msk397 (machangxinq@gmail.com)
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"""
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class Pair:
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"""Key-value pair"""
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def __init__(self, key: int, val: str):
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self.key = key
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self.val = val
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class ArrayHashMap:
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"""Hash table implemented with an array"""
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def __init__(self):
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"""Constructor"""
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# Initialize an array containing 100 buckets
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self.buckets: list[Pair | None] = [None] * 100
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def hash_func(self, key: int) -> int:
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"""Hash function"""
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index = key % 100
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return index
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def get(self, key: int) -> str | None:
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"""Lookup operation"""
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index: int = self.hash_func(key)
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pair: Pair = self.buckets[index]
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if pair is None:
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return None
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return pair.val
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def put(self, key: int, val: str):
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"""Insert and update operations"""
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pair = Pair(key, val)
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index: int = self.hash_func(key)
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self.buckets[index] = pair
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def remove(self, key: int):
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"""Remove operation"""
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index: int = self.hash_func(key)
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# Set to None to mark removal
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self.buckets[index] = None
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def entry_set(self) -> list[Pair]:
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"""Get all key-value pairs"""
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result: list[Pair] = []
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for pair in self.buckets:
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if pair is not None:
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result.append(pair)
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return result
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def key_set(self) -> list[int]:
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"""Get all keys"""
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result = []
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for pair in self.buckets:
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if pair is not None:
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result.append(pair.key)
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return result
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def value_set(self) -> list[str]:
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"""Get all values"""
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result = []
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for pair in self.buckets:
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if pair is not None:
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result.append(pair.val)
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return result
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def print(self):
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"""Print the hash table"""
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for pair in self.buckets:
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if pair is not None:
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print(pair.key, "->", pair.val)
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"""Driver code"""
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if __name__ == "__main__":
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# Initialize the hash table
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hmap = ArrayHashMap()
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# Insert operation
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# Insert the key-value pair (key, value) into the hash table
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hmap.put(12836, "小哈")
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hmap.put(15937, "小啰")
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hmap.put(16750, "小算")
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hmap.put(13276, "小法")
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hmap.put(10583, "小鸭")
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print("\nHash table after insertion:\nKey -> Value")
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hmap.print()
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# Lookup operation
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# Look up key in the hash table to obtain value
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name = hmap.get(15937)
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print("\nLook up student ID 15937 to obtain the name " + name)
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# Remove operation
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# Remove the key-value pair (key, value) from the hash table
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hmap.remove(10583)
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print("\nHash table after removing 10583:\nKey -> Value")
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hmap.print()
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# Traverse the hash table
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print("\nTraverse key-value pairs: Key->Value")
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for pair in hmap.entry_set():
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print(pair.key, "->", pair.val)
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print("\nTraverse keys only: Key")
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for key in hmap.key_set():
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print(key)
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print("\nTraverse values only: Value")
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for val in hmap.value_set():
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print(val)
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