Untitled

package Autocomplete;

import java.util.ArrayList;
import java.util.HashMap;

class UserSolution {
    private static final int ALPHABET_SIZE = 26;
    private final HashMap<String, Word> mapWord = new HashMap<>();
    private Trie root;
    private int order;

    void init() {
        mapWord.clear();
        root = new Trie();
        order = 0;
    }

    void inputWord(char[] mWord) {
        order++;
        String str = new String(mWord).trim();
        Word word = mapWord.get(str);
        if (word == null) {
            word = new Word(str, order);
            mapWord.put(str, word);
            Trie temp = root;
            for (char c : str.toCharArray()) {
                int index = c - 'a';
                if (temp.node[index] == null) {
                    temp.node[index] = new Trie();
                }
                temp = temp.node[index];
                temp.list.add(word);
            }
        } else {
            if (word.count == 0)
                return;
            word.count++;
            word.order = order;
        }
    }

    int recommend(char[] mUser, char[] mAnswer) {
        String str = new String(mUser).trim();
        Trie temp = root;
        for (char c : str.toCharArray()) {
            int index = c - 'a';
            if (temp.node[index] == null) {
                output(str, mAnswer);
                return str.length();
            }
            temp = temp.node[index];
        }
        String res = temp.findWord(str);
        output(res, mAnswer);
        return res.length();
    }

    void output(String str, char[] mAnswer) {
        System.arraycopy(str.toCharArray(), 0, mAnswer, 0, str.length());
        mAnswer[str.length()] = '\0';
    }

    void banWord(char[] mWord) {
        String str = new String(mWord).trim();
        Word word = mapWord.get(str);
        if (word != null) {
            word.count = 0;
        } else {
            word = new Word(str, order);
            word.count = 0;
            mapWord.put(str, word);
        }
    }

    static class Word {
        final String str;
        int count;
        int order;

        public Word(String str, int order) {
            this.str = str;
            this.count = 1;
            this.order = order;
        }
    }

    static class Trie {
        final ArrayList<Word> list = new ArrayList<>();
        final Trie[] node = new Trie[ALPHABET_SIZE];

        String findWord(String str) {
            Word res = new Word(str, Integer.MAX_VALUE);
            res.count = 0;
            for (Word word : list) {
                if (word.count > res.count || (word.count == res.count && word.order > res.order)) {
                    res = word;
                }
            }
            return res.str;
        }
    }
}