public class DemoExpression {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		
		Expression exp = new AddExp(new IntExp(4),new AddExp(new IntExp(2),new IntExp(5)) );
		System.out.println(exp.show() + " : " + exp.eval());
exp.traverse();
	}

}