public class Regex1 {
    public static void main(String[] args) {
       String s = "神秘的海洋出现了一只#话题#海怪阿拉斯加#热门话题#和一艘很诡异的破船\n";
       System.out.println("例子："+s);
       Pattern pattern = Pattern.compile("#(.*?)#");
       Matcher matcher = pattern.matcher(s);
       while (matcher.find()){
           System.out.println(matcher.group(1));
       }
       System.out.println(s.replaceAll("#(.*?)#",""));
    }
}