62 lines
1.6 KiB
Python
62 lines
1.6 KiB
Python
# Time: O(N / K) ; N is num of all keys and K is num of predefined buckets
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# Space: O(K + M) ; K is num of predefined buckets and M is no. of unique
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# keys inserted
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from collections import deque
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class MyHashMap:
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def __init__(self):
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# TODO: Better hash function and better initial capacity needed
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# Maybe initial capacity can even be passed as an option?
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self.store = [Bucket()] * 997
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def put(self, key: int, value: int) -> None:
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i = self._hash(key)
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self.store[i].upsert(key, value)
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def get(self, key: int) -> int:
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i = self._hash(key)
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pair = self.store[i].get_pair(key)
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return pair[1] if pair else -1
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def remove(self, key: int) -> None:
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i = self._hash(key)
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return self.store[i].remove(key)
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def _hash(self, key: int):
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# TODO: Note down better hash functions
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return key % 997
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class Bucket:
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def __init__(self):
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self.d = deque()
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def upsert(self, key, value):
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pair = self.get_pair(key)
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if pair is not None:
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pair[1] = value
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else:
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self.d.append([key, value])
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def get_pair(self, key):
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for item in self.d:
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if item[0] == key:
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return item
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def remove(self, key):
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item = self.get_pair(key)
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if item is not None:
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self.d.remove(item)
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# Your MyHashMap object will be instantiated and called as such:
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# obj = MyHashMap()
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# obj.put(key,value)
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# param_2 = obj.get(key)
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# obj.remove(key)
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