/** An instance has a method to change a Worker's social security number.*/
// Students: see what happens when you try to compile this file.
public class Gremlin {
    
    /** = w's SSN */
    public int getSSN(Worker w) {
        return w.ssn;
    }
    
    
    /** Overwrite w's SSN with the value 13. */
    public void overwriteSSN(Worker w) {
        w.ssn= 13; // guess that the SSN is in a field called ssn
    }
}