text: // assuming include of <string> and using the same namespace
  
  class Employee : public Person {
    private:
  	int staffNumber;
    
    public:
  	Employee(string firstName, string lastName, int age, int staffNumber) {
  		Person::(firstName, lastName, age);
  		this.staffNumber = staffNumber;
  	}
  	
  	~Employee();
    
  	string toString() {
  		return Person::toString() + ", " + this.staffNumber;
  	}
  };