Implement Trie (Prefix Tree) - Python Solution

 Implement a trie with insert, search, and startsWith methods.

Example:

Trie trie = new Trie();

trie.insert("apple");
trie.search("apple");   // returns true
trie.search("app");     // returns false
trie.startsWith("app"); // returns true
trie.insert("app");   
trie.search("app");     // returns true
class TrieNode:
    def __init__(self):
        self.word = False
        self.children = {}
class Trie:

    def __init__(self):
        """
        Initialize your data structure here.
        """
        self.root = TrieNode()
        

    def insert(self, word: str) -> None:
        """
        Inserts a word into the trie.
        """
        node = self.root
        for w in word:
            if w not in node.children:
                node.children[w] = TrieNode()
            node = node.children[w]
        node.word = True
        

    def search(self, word: str) -> bool:
        """
        Returns if the word is in the trie.
        """
        node = self.root
        for w in word:
            if w not in node.children:
                return False
            node = node.children[w]
        return node.word

    def startsWith(self, prefix: str) -> bool:
        """
        Returns if there is any word in the trie that starts with the given prefix.
        """
        node = self.root
        for p in prefix:
            if p not in node.children:
                return False
            node = node.children[p]
        return True
        


# Your Trie object will be instantiated and called as such:
# obj = Trie()
# obj.insert(word)
# param_2 = obj.search(word)
# param_3 = obj.startsWith(prefix)

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