Exception in thread "main" java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Integer
at java.lang.Integer.compareTo(Integer.java:52)
at java.util.TreeMap.put(TreeMap.java:568)
at java.util.TreeSet.add(TreeSet.java:255)
at TKO.before(Main.java:13)
at TKO.main(Main.java:7)