import java.util.*;

class Demo {

    static Object max(Collection bag) {
	Object max = null;
	Iterator i = bag.iterator();
	if (i.hasNext())
	    max = i.next();
	while (i.hasNext()) {
	    Comparable item = (Comparable)i.next();
	    if (item.compareTo(max) > 0)
		max = item;
	}
	return max;
    }

    public static void main(String[] args) {
	Collection names = new ArrayList();

	names.add("Mark");
	names.add("John");
	names.add("Mary");
	names.add("Jane");
	names.add("John");
	names.add("Mary");
	System.out.println(names);

	names.remove("Mary");
	System.out.println(names);

	System.out.println(max(names));

	Collection nums = new HashSet();
	nums.add(new Integer(2));
	nums.add(new Integer(64));
	nums.add(new Integer(16));
	nums.add(new Integer(32));
	nums.add(new Integer(8));
	nums.add(new Integer(64));
	nums.add(new Integer(16));
	System.out.println(nums);

	nums.remove(new Integer(16));
	nums.remove(new Integer(64));
	System.out.println(nums);

	System.out.println(max(nums));
    }
}