71 lines
1.3 KiB
Python
71 lines
1.3 KiB
Python
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class Node:
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def __init__(self):
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self.children = {} # the children that this node points to
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self.endofword = False
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class Trie:
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def __init__(self):
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self.root = Node()
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def insert(self, word: str) -> None:
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ptr = self.root
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for letter in word:
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if letter not in ptr.children:
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ptr.children[letter] = Node()
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# traverse down the tree
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ptr = ptr.children[letter]
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ptr.endofword = True
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def search(self, word: str) -> bool:
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ptr = self.root
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for letter in word:
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if letter not in ptr.children:
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return False
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ptr = ptr.children[letter]
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# check end of word?
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if ptr.endofword:
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return True
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else:
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return False
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def startsWith(self, prefix: str) -> bool:
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ptr = self.root
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for letter in prefix:
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if letter not in ptr.children:
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return False
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ptr = ptr.children[letter]
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return True
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trie = Trie();
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output = []
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output.append( trie.insert("apple") )
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output.append( trie.search("apple") )
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output.append( trie.search("app") )
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output.append( trie.startsWith("app") )
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output.append( trie.insert("app") )
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output.append( trie.search("app") )
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print(output)
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