208. Implement Trie (Prefix Tree)

class TrieNode(object):
    def __init__(self):
        """
        Initialize your data structure here.
        """
        self.isString=False
        self.leaves={}
        

class Trie(object):

    def __init__(self):
        self.root = TrieNode()

    def insert(self, word):
        """
        Inserts a word into the trie.
        :type word: str
        :rtype: void
        """
        cur=self.root
        for c in word:
            if c not in cur.leaves:
                cur.leaves[c]=TrieNode()
            cur=cur.leaves[c]
            
        cur.isString=True
        

    def search(self, word):
        """
        Returns if the word is in the trie.
        :type word: str
        :rtype: bool
        """
        node=self.searchChild(word)
        if node:
            return node.isString
        return False
        

    def startsWith(self, prefix):
        """
        Returns if there is any word in the trie
        that starts with the given prefix.
        :type prefix: str
        :rtype: bool
        """
        if self.searchChild(prefix): return True
        return False
    def searchChild(self,word):
        cur=self.root
        for c in word:
            if c not in cur.leaves:
                return None
            else:
                cur=cur.leaves[c]
        return cur
            

# Your Trie object will be instantiated and called as such:
# trie = Trie()
# trie.insert("somestring")
# trie.search("key")