定义学生类Student ，用于存放并输出学生的姓名、学号、年龄、程序设计的成绩并统计学生人数。

1) 定义缺省构造函数、带参数的构造函数和拷贝构造函数给学生的姓名、学号、年龄、程序设计的成绩分配内存并赋值；

2) 定义函数输出学生信息；

3）定义析构函数；

4) 在主函数中定义多个对象并调用上述成员函数进行测试；

5)采用头文件和源文件对程序进行组织。

-Define the student class Student, used to store and output the student' s name, student number, age, and the results of the program design and statistics the number of students. 1) define a default constructor, constructor and copy constructor parameters to the student' s name, student number, age, the results of procedures designed to allocate memory and assign　2) defines the function output of student information　3) define a destructor　 4) in the main function definition of multiple objects and call these member functions to be tested　5) the header files and source files to organize the program.