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

class TrieNode {
    boolean storeWord = false;
    TrieNode[] children = new TrieNode[26];
}
public class Solution {
    TrieNode root = new TrieNode();

    public void insert (String word) {
        TrieNode curr = root;
        for (char c : word.toCharArray()) {
            if (curr.children[c - 'a'] == null) {
                curr.children[c - 'a'] = new TrieNode();
            }
            curr = curr.children[c - 'a'];
        }
        curr.storeWord = true;
    }

    public boolean search (String word) {
        TrieNode curr = root;
        for (char c : word.toCharArray()) {
            if (curr.children[c - 'a'] == null) {
                return false;
            }
            curr = curr.children[c - 'a'];
        }
        return curr.storeWord;
    }

    public boolean startsWith(String prefix) {
        TrieNode curr = root;
        for (char c : prefix.toCharArray()) {
            if (curr.children[c - 'a'] == null) {
                return false;
            }
            curr = curr.children[c - 'a'];
        }
        return true;
    }
}

class TrieNode(object):

    def __init__(self):
        self.is_word = False
        self.children = {}

class Trie(object):

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

    def insert(self, word):
        """
        Inserts a word into the trie.
        :type word: str
        :rtype: void
        """
        curr = self.root
        for char in word:
            if char not in curr.children:
                curr.children[char] = TrieNode()
            curr = curr.children[char]
        curr.is_word = True

    def search(self, word):
        """
        Returns if the word is in the trie.
        :type word: str
        :rtype: bool
        """
        curr = self.root
        for char in word:
            if char not in curr.children:
                return False
            curr = curr.children[char]
        return curr.is_word

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