. Construction method: nonparametric construction method, parametric construction method

3. Member method: getxxx method, setXXX method, display basic information, showmsg method

Define the teacher class and inherit person

1. Attribute: Discipline

2. Construction method: nonparametric construction method, parametric construction method

3. Member method: getxxx method, setXXX method, lecture method

Define student class and inherit person

1. Attribute: Score

2. Construction method: nonparametric construction method, parametric construction method

3. Member method: getxxx method, setXXX method, examination method

Define test4 test class, test showmsg method, lecture method and examination method.