60. 匹配前缀的词典

import java.util.Scanner;

// 字典树的节点
class TrieNode {
    boolean isWord;
    final TrieNode[] children;
    public TrieNode() {
        isWord = false;
        children = new TrieNode[26];
    }
}

// 字典树
class Trie {
    TrieNode root;

    Trie() {
        root = new TrieNode();
    }

    public void insert(String word) {
        TrieNode current = root;
        for (int i = 0; i < word.length(); i++) {
            int c = word.charAt(i) - 'a';
            if (current.children[c] == null) {
                current.children[c] = new TrieNode();
            }
            current = current.children[c];
        }
        current.isWord = true;
    }

//    完整的字段树应该包含搜索功能，但是此处用不到
//    public boolean search(String word) {
//        TrieNode current = root;
//        for (int i = 0; i < word.length(); i++) {
//            int c = word.charAt(i) - 'a';
//            if (current.children[c] == null) {
//                return false;
//            }
//            current = current.children[c];
//        }
//        return current.isWord;
//    }

    public boolean startWith(String word) {
        TrieNode current = root;
        for (int i = 0; i < word.length(); i++) {
            int c = word.charAt(i) - 'a';
            if (current.children[c] == null) {
                return false;
            }
            current = current.children[c];
        }
        return true;
    }
}

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int m = scanner.nextInt();
        int n = scanner.nextInt();

        scanner.nextLine(); // 消耗掉换行符
        Trie trie = new Trie();
        for (int i = 0; i < m; i++) {
            trie.insert(scanner.nextLine());
        }

        for (int i = 0; i < n; i++) {
            boolean isStart = trie.startWith(scanner.nextLine());
            System.out.println(isStart);
        }
    }
}