211.Add and Search Word - Data structure design

class WordDictionary {
    private TrieNode root;

    /** Initialize your data structure here. */
    public WordDictionary() {
        this.root = new TrieNode();
    }

    /** Adds a word into the data structure. */
    public void addWord(String word) {
        TrieNode curNode = root;
        for(char c : word.toCharArray()){
            if(curNode.children[c - 'a'] == null){
                curNode.children[c - 'a'] = new TrieNode();
            }
            curNode = curNode.children[c - 'a'];
        }
        curNode.isWord = true;
    }

    /** Returns if the word is in the data structure. A word could contain the dot character '.' to represent any one letter. */
    public boolean search(String word) {
        return match(word.toCharArray(), 0, root);
    }

    private boolean match(char[] chs, int k, TrieNode node){
        if(k == chs.length){
            return node.isWord;
        }
        if(chs[k] == '.'){
            for(int i = 0; i < node.children.length; i++){
                if(node.children[i] != null && match(chs, k + 1, node.children[i]))
                    return true;
            }
        }
        else{
            return node.children[chs[k] - 'a'] != null && match(chs, k + 1, node.children[chs[k] - 'a']);
        }
        return false;
    }
}

class TrieNode{
    public TrieNode[] children = new TrieNode[26];
    public boolean isWord;
}

/**
 * Your WordDictionary object will be instantiated and called as such:
 * WordDictionary obj = new WordDictionary();
 * obj.addWord(word);
 * boolean param_2 = obj.search(word);
 */

https://leetcode.com/problems/add-and-search-word-data-structure-design/discuss/59554

public class WordDictionary {

    public class TrieNode {
        public TrieNode[] children = new TrieNode[26];
        public boolean isWord;
    }

    private TrieNode root = new TrieNode();

    // Adds a word into the data structure.
    public void addWord(String word) {
        TrieNode node = root;
        for (char c : word.toCharArray()) {
            if (node.children[c - 'a'] == null) {
                node.children[c - 'a'] = new TrieNode();
            }
            node = node.children[c - 'a'];
        }
        node.isWord = true;
    }

    // Returns if the word is in the data structure. A word could
    // contain the dot character '.' to represent any one letter.
    public boolean search(String word) {
        return match(word.toCharArray(), 0, root);
    }

    private boolean match(char[] chs, int k, TrieNode node) {
        if (k == chs.length) {
            return node.isWord;
        }
        if (chs[k] == '.') {
            for (int i = 0; i < node.children.length; i++) {
                if (node.children[i] != null && match(chs, k + 1, node.children[i])) {
                    return true;
                }
            }
        } else {
            return node.children[chs[k] - 'a'] != null && match(chs, k + 1, node.children[chs[k] - 'a']);
        }
        return false;
    }
}