题解 | #合唱队#

就是这么暴力....

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        // 注意 hasNext 和 hasNextLine 的区别
        while (in.hasNext()) { // 注意 while 处理多个 case
            int n = in.nextInt();
            String[] arr = new String[n];
            // 3 abc bca cab abc 1
            for (int i = 0; i < n; i++) {
                arr[i] = in.next();
            }
            String x = in.next();
            int k = in.nextInt();
            String[] brotherWord = findBrother(x, arr);
            System.out.println(brotherWord.length);
            if (k - 1 < brotherWord.length) {
                System.out.println(brotherWord[k - 1]);
            }
        }
    }

    private static String[] findBrother(String x, String[] arr) {
        if (arr == null || arr.length == 0 || x == null) {
            return new String[0];
        }
        List<String> temp = new ArrayList<>();
        for (String s : arr) {
            if (!s.equals(x) && isBrother(s, x)) {
                temp.add(s);
            }
        }
        temp.sort(String::compareTo);
        temp.forEach(System.out::println);
        String[] ret = new String[temp.size()];
        temp.toArray(ret);
        return ret;

    }

    private static boolean isBrother(String s, String x) {
        if (s == null || x == null || s.length() != x.length()) {
            return false;
        }

        for (char c : s.toCharArray()) {
            if (!x.contains(c + "")) {
                return false;
            }
        }

        for (char c : x.toCharArray()) {
            if (!s.contains(c + "")) {
                return false;
            }
        }

        // 取出每一个字母的次数 不一样就不是
        Map<String, Integer> maps = new HashMap<>(s.length());

        for (char c : s.toCharArray()) {
            if (!maps.containsKey(c + "")) {
                maps.put(c + "", 1);
            } else {
                maps.put(c + "", maps.get(c + "") + 1);
            }
        }
        Map<String, Integer> mapx = new HashMap<>(x.length());
        for (char c : x.toCharArray()) {
            if (!mapx.containsKey(c + "")) {
                mapx.put(c + "", 1);
            } else {
                mapx.put(c + "", mapx.get(c + "") + 1);
            }
        }
        for (Map.Entry<String, Integer> entry:maps.entrySet()){
            if(!mapx.containsKey(entry.getKey()) || mapx.get(entry.getKey()).intValue()!=entry.getValue().intValue()){
                return false;
            }
        }
        for (Map.Entry<String, Integer> entry : mapx.entrySet()) {
            if(!maps.containsKey(entry.getKey()) || maps.get(entry.getKey()).intValue()!=entry.getValue().intValue()){
                return false;
            }
        }

        return true;
    }