208-Trie树

class Trie {
    static class Node{
        boolean end =false;
        Node []son =new Node[26];
    }
    Node root =new Node();
    public Trie() {
        
    }
    public void insert(String word) {
        Node curr =root;
        for(char arr:word.toCharArray()){
            arr -='a';
            if(curr.son[arr] == null){
                curr.son[arr] =new Node();
            }
            curr = curr.son[arr];
        }   
        curr.end =true;
    }
    
    public boolean search(String word) {
        return getTrie(word)==2;
    }
    
    public boolean startsWith(String prefix) {
        return getTrie(prefix)!=0;
    }
    int getTrie(String word){
        Node arr =root;
        for(char now:word.toCharArray()){
            now-='a';
            if(arr.son[now]==null){
                return 0;
            }
            arr = arr.son[now];
        }
        return arr.end == true?2:1;
    }
}

/**
 * Your Trie object will be instantiated and called as such:
 * Trie obj = new Trie();
 * obj.insert(word);
 * boolean param_2 = obj.search(word);
 * boolean param_3 = obj.startsWith(prefix);
 */