题目描述：

编写两个有意义的类，使一个类嵌套在另一个类中。

分析：

本题涉及两个类student和cdegree，前者为学生类，包含学生的学号(nubner)，姓名（name）和成绩(degree)，而成绩degree是类cdegree的对象。cdegree类有3个数据成员，分别为数学(math)，英语(english)和物理(phy)分数。

程序代码：

#include<iostream>
#include<string>
using namespace std;
class Student 
{
	public:
		void getdata();
		void showdata();
	private:
		string number;
		string name;
		class Cdegree
		{
			public:
				double math;
				double english;
				double phy;
		}degree;				
};
void Student::getdata() 
{
	cout<<"Input number:";
	cin>>number;
	cout<<"Input name:";
	cin>>name;
	cout<<"Input degree of math:";
	cin>>degree.math;
	cout<<"Input degree of english:";
	cin>>degree.english;
	cout<<"Input degree of physics:";
	cin>>degree.phy; 
}
void Student::showdata()
{
	cout<<"=========分割线======="<<endl; 
	cout<<"Number:"<<number<<endl;
	cout<<"Name:"<<name<<endl;
	cout<<"Math"<<degree.math<<endl;
	cout<<"English:"<<degree.english<<endl;
	cout<<"Physics:"<<degree.phy<<endl; 
}
int main()
{
	Student s1;
	s1.getdata();
	s1.showdata();
	return 0;
}

结果输出：

Input number:007
Input name:qianshou
Input degree of math:89
Input degree of english:99
Input degree of physics:100
=========分割线=======
Number:007
Name:qianshou
Math89
English:99
Physics:100