/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	
	public static void main (String[] args) throws java.lang.Exception
	{
		Set<String> a = new TreeSet<>(String.CASE_INSENSITIVE_ORDER);
		SortedSet<String> b = new TreeSet<>(String.CASE_INSENSITIVE_ORDER);
		populate(a);
		show(a, "Original a");
		populate(b);
		show(b, "Original b");
		Set<String> copyA = new TreeSet<String>(a);
		show(copyA, "Copy of a");
		Set<String> copyB = new TreeSet<String>(b);
		show(copyB, "Copy of b");
	}
	static void populate(Set<String> s) {
		s.add("A");
		s.add("aa");
		s.add("B");
		s.add("bb");
	}
	static void show(Set<String> s, String name) {
		System.out.println("============ "+name+" ==========");
		for (String t : s) {
			System.out.println(t);
		}
	}
}