多继承（研究生类）

#include<iostream>
using namespace std;
#include<string>;
class People
{
public:
	People(const string& name,const string& sex, int age)
		:_name(name)
		, _sex(sex)
		, _age(age)
	{

	}
	virtual void Display()
	{
		cout << "name: " << _name << endl;
		cout << "sex: " << _sex << endl;
		cout << "age: " << _age << endl;
	}
protected:
	string _name;
	string _sex;
	int _age;
};
class Student:virtual public People
{
public:
	Student(const string& name, const string& sex, int age, int num)
		:People(name,sex,age)
		, _num(num)
	{

	}
	virtual void Display()
	{
		cout << "Student" << endl;
	}
protected:
	int _num;
};
class Teacher:virtual public People
{
public:
	Teacher(const string& name, const string& sex, int age, int employeeNumber)
		:People(name, sex, age)
		, _employeeNumber(employeeNumber)
	{

	}
	virtual void Display()
	{
		cout << "Teacher" << endl;
	}
protected:
	int _employeeNumber;
};
class Graduate:public Teacher,public Student
{
public:
	Graduate(const string& name, const string& sex, int age, int employeeNumber, int num,const string& learnClass)
		:People(name, sex, age)
		, Teacher(name, sex, age,employeeNumber)
		, Student(name,sex,age,num)
	{
		_learnClass = learnClass;
	}
	virtual void Display()
	{
		cout << "Graduate" << endl;
	}
protected:
	string _learnClass;//研究科目
};
void Test1()
{
	People p("lxj", "女", 18);
	People* p1 = &p;
	p.Display();
	p1->Display();

	Student s("lt", "女", 21, 413);
	p1 = &s;//p1=(People*)&s;
	p1->Display();
}
void Test2()
{
	People p("lxj", "女", 18);
	People& p1 = p;
	p.Display();
	p1.Display();

	Student s("lt", "女", 21, 413);
	People& p2 =(People&) s;

	s.Display();
	p2.Display();
}
void Test3()
{
	Graduate  g("lxj", "女", 11, 22, 11, "software");
	g.Display();
}
int main()
{
	Test3();
	system("pause");
	return 0;
}