ArrayList al=new ArrayList();
al.add("A");
al.add(10);
al.add("A");
al.add(null);
System.out.println(al);
al.remove(2);
System.out.println(al);
System.out.println(al.get(2));
al.add(2,"M"); // here
System.out.println(al);
al.add("N");