定义一个score类，其中包括私有数据成员和公有成员函数，即

num 学号

Math 高等数学成绩

English 英语成绩

Programming 程序设计成绩

inscore() 输入学号和各科成绩，并且计算平均成绩

showscore(时) 输出学号和各科成绩

使用score类，输入某班n（事先不能确定）个学生的学号和各科成绩，然后求各个学生的平均成绩，并列表输出学生的学号、各科成绩和平均成绩。

-Define a score class, including private data members and public member functions, that is, num number Math Science English to score higher in math achievement Programming Programming inscore () input student number and all subjects, and calculated the average score showscore () Output Student ID and all subjects using the score class, enter a class n (can not determine in advance) a student' s student number and all subjects, and then find each student' s grade point average, and list the output numbers of school students, all subjects and the average results.