一段C++程序 谁给改改错误 大体解释下程序 谢谢哥哥！

#include <iostream>
#include <string>
using namespace std;

class person
{
public :
person(string name = "", string id = ""):m_name(name), m_id(id){}
virtual string get() const {return m_name;}//虚函数
~person(){}
protected :
string m_name;//姓名
string m_id;//身份证号
};

class student:public person//类的继承
{
friend istream & operator >> (istream &in, student &stu);//友元运算符重载
public :
student(string name = "", string id = "", string num = ""):person(name, id), m_num(num){}
string get() const {return m_num;}
private :
string m_num;//学号
};
istream & operator >> (istream &in, student &stu)
{
cout << "input student infomation:" << endl;
cout << "name:";
in >> stu.m_name;
cout << "id:";
in >&

改改这道C程序 谁帮我改改这个C语言程序啊? 帮我改改C语言的错误 高分奖励请人指点一段C程序错误 一段c的程序 一段小C程序 求助一段C程序 这一段C程序出了什么问题？谁能给我讲明白 c语言程序错误 c程序错误