public class StackTest {
    public static void main(String[] args) {
	Stack<Double> s1 = new StackOfDoubles();
	Stack<Double> s2 = new StackOfDoubles();

        System.out.println("sl empty? " + s1.isEmpty());
	System.out.println("s2 empty? " + s2.isEmpty());

	s1.push(1.2);
	s1.push(3.4);
	s1.push(5.6);
	s1.push(7.8);

	System.out.println(s1.peek());

	System.out.println("sl empty? " + s1.isEmpty());
	System.out.println("s2 empty? " + s2.isEmpty());

	while(!s1.isEmpty()) {
	    double val = s1.pop();
	    System.out.println(val);
	    s2.push(val);
	}
	System.out.println("sl empty? " + s1.isEmpty());
	System.out.println("s2 empty? " + s2.isEmpty());
	while(!s2.isEmpty()) {
	    System.out.println(s2.pop());
	}
    }
}