题解 | #查找兄弟单词#

import java.util.*;
import java.io.*;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader bf = new BufferedReader(new InputStreamReader(System.in));
        String line = null;
        while((line = bf.readLine()) != null){
            String[] words = line.split(" ");
            int n = Integer.parseInt(words[0]);
            int t = mCode(words[n + 1]);
            ArrayList<String> brothers = new ArrayList<String>();
            for (int i = 1; i <= n; ++i) {
                if (!words[i].equals(words[n + 1]) && mCode(words[i]) == t) {
                    brothers.add(words[i]);
                }
            }
            brothers.sort(Comparator.naturalOrder());
            
            int which = Integer.parseInt(words[n + 2]);
            int size = brothers.size();
            System.out.println(size);
            if (size >= which) {
                System.out.println(brothers.get(which - 1));
            }
        }
    }
    
    public static int mCode(String word) {
        int mCode = 1;
        for (int i = 0; i < word.length(); ++i) {
            mCode *= word.charAt(i);
        }
        return mCode;
    }
}