import java.util.EmptyStackException;
import java.util.Stack;
class StackDemo {
static void showpush(Stack st, int a) {
st.push(a);
System.out.println("push(" + a + ")");
System.out.println("stack: " + st);
}
static void showpop(Stack st) {
System.out.print("pop -> ");
Integer a = st.pop();
System.out.println(a);
System.out.println("stack: " + st);
}
public static void main(String args[]) {
Stack st = new Stack();
System.out.println("stack: " + st);
showpush(st, 42);
showpush(st, 66);
showpush(st, 99);
showpop(st);
try {
showpop(st);
} catch (EmptyStackException e) {
System.out.println("empty stack");
}
}
}