/**
* SubExp: it is extended from the abstract class Exp,
* This class is used to represent the expression of subtraction
*
* Please do not change anything else.
*/
public class SubExp extends Exp {
private Exp term;
private Exp exp;
public SubExp(Exp term, Exp exp) {
this.term = term;
this.exp = exp;
}
@Override
public String show() {
return “(” + term.show() + ” – ” + exp.show() + “)”;
}
@Override
public int evaluate() {
return (term.evaluate() – exp.evaluate());
}
}