import java.util.*;

public class TreeSetExample{
	public static void main(String[] args) {
		System.out.println("Tree Set Example!\n");
		TreeSet <Integer>tree = new TreeSet<Integer>();
		tree.add(12);
		tree.add(23);
		tree.add(34);
		tree.add(45);
		Iterator iterator;
		iterator = tree.iterator();
		System.out.print("Tree set data: ");
		//Displaying the Tree set data
		while (iterator.hasNext()){
			System.out.print(iterator.next() + " ");
		}
		System.out.println();
		//Check impty or not
		if (tree.isEmpty()){
			System.out.print("Tree Set is empty.");
		}
		else{
			System.out.println("Tree Set size: " + tree.size());
		}
		//Retrieve first data from tree set
		System.out.println("First data: " + tree.first());
		//Retrieve last data from tree set
		System.out.println("Last data: " + tree.last());
		if (tree.remove(30)){
			System.out.println("Data is removed from tree set");
		}
		else{
			System.out.println("Data doesn't exist!");
		}
		System.out.print("Now the tree set contain: ");
		iterator = tree.iterator();
		//Displaying the Tree set data
		while (iterator.hasNext()){
			System.out.print(iterator.next() + " ");
		}
		System.out.println();
		System.out.println("Now the size of tree set: " + tree.size());
		//Remove all
		tree.clear();
		if (tree.isEmpty()){
			System.out.print("Tree Set is empty.");
		}
		else{
			System.out.println("Tree Set size: " + tree.size());
		}
	}
}