#include <iostream>
using namespace std;
class Person
{
public:
	void Print()
	{
		cout << "name:" << _name << endl;
		cout << "age:" << _age << endl;
	}
protected:
	string _name = "peter"; // 姓名
	int _age = 18; // 年齡
};
// 繼承后父類的Person的成員（成員函數(shù)+成員變量）都會變成子類的一部分。這里體現(xiàn)出了
//Student和Teacher復(fù)用了Person的成員。
class Student : public Person
{
protected:
	int _stuid; // 學號
};
 
class Teacher : public Person
{
protected:
	int _jobid; // 工號
};
int main()
{
	Student s;
	Teacher t;
	s.Print();
	t.Print();
	return 0;
}

#include <iostream>
using namespace std;
class Person
{
protected:
	string _name; // 姓名
	string _sex; // 性別
	int _age; // 年齡
};
class Student : public Person
{
public:
	int _No; // 學號
};
void Test()
{
	Student sobj;
	// 1.子類對象可以賦值給父類對象/指針/引用
	Person pobj = sobj;
	Person* pp = &sobj;
	Person& rp = sobj;
 
	//2.基類對象不能賦值給派生類對象
	//sobj = pobj;
	
	// 3.基類的指針可以通過強制類型轉(zhuǎn)換賦值給派生類的指針
	pp = &sobj;
	Student * ps1 = (Student*)pp; // 這種情況轉(zhuǎn)換時可以的。
	ps1->_No = 10;
	pp = &pobj;
	Student* ps2 = (Student*)pp; // 這種情況轉(zhuǎn)換時雖然可以，但是會存在越界訪問的問題
	ps2->_No = 10;
}

// Student的_num和Person的_num構(gòu)成隱藏關(guān)系，可以看出這樣代碼雖然能跑，但是非常容易混淆
class Person
{
protected:
	string _name = "小李子"; // 姓名
	int _num = 111; // 身份證號
};
class Student : public Person
{
public:
	void Print()
	{
		cout << " 姓名:" << _name << endl;
		cout << " 身份證號:" << Person::_num << endl;
		cout << " 學號:" << _num << endl;
	}
protected:
	int _num = 999; // 學號
};
void Test1()
{
	Student s1;
	s1.Print();
};
 
// B中的fun和A中的fun不是構(gòu)成重載，因為不是在同一作用域
// B中的fun和A中的fun構(gòu)成隱藏，成員函數(shù)滿足函數(shù)名相同就構(gòu)成隱藏。
class A
{
public:
	void fun()
	{
		cout << "func()" << endl;
	}
};
class B : public A
{
public:
	void fun(int i)
	{
		A::fun();
		cout << "func(int i)->" << i << endl;
	}
};
void Test2()
{
	B b;
	b.fun(10);
};
int main()
{
	Test1();
	Test2();
	return 0;
}

class Person
{
public:
	Person(const char* name = "peter"): _name(name)
	{
		cout << "Person()" << endl;
	}
 
	Person(const Person& p)	: _name(p._name)
	{
		cout << "Person(const Person& p)" << endl;
	}
 
	Person& operator=(const Person & p)
	{
		cout << "Person operator=(const Person& p)" << endl;
		if (this != &p)
		{
			_name = p._name;
		}
		return *this;
	}
 
	~Person()
	{
		cout << "~Person()" << endl;
	}
 
protected:
	string _name; // 姓名
};
class Student : public Person
{
public:
	Student(const char* name, int num): Person(name), _num(num)
	{
		cout << "Student()" << endl;
	}
 
	//派生類的拷貝構(gòu)造函數(shù)必須調(diào)用基類的拷貝構(gòu)造完成基類的拷貝初始化
	Student(const Student& s): Person(s), _num(s._num)
	{
		cout << "Student(const Student& s)" << endl;
	}
 
	//派生類的operator=必須要調(diào)用基類的operator=完成基類的復(fù)制
	Student& operator = (const Student& s)
	{
		cout << "Student& operator= (const Student& s)" << endl;
		if (this != &s)
		{
			Person::operator =(s);
			_num = s._num;
		}
		return *this;
	}
 
	~Student()
	{
		cout << "~Student()" << endl;
	}
 
protected:
	int _num; //學號
};
void Test()
{
	Student s1("jack", 18); 
	Student s2(s1);
	Student s3("rose", 17);
	s1 = s3;
}
 
int main()
{
	Test();
	return 0;
}

class Person
{
public:
	Person() 
	{
		++_count;
	}
protected:
	string _name; // 姓名
public:
	static int _count; // 統(tǒng)計人的個數(shù)。
};
int Person::_count = 0;
 
class Student : public Person
{
protected:
	int _stuNum; // 學號
};
class Graduate : public Student
{
protected:
	string _seminarCourse; // 研究科目
};
void TestPerson()
{
	Student s1;
	Student s2;
	Student s3;
	Graduate s4;
	cout << " 人數(shù) :" << Person::_count << endl;
	Student::_count = 0;
	cout << " 人數(shù) :" << Person::_count << endl;
}
 
 
int main()
{
	TestPerson();
	return 0;
}

class Person
{
public:
	string _name; // 姓名
};
 
class Student : virtual public Person
{
protected:
	int _num; //學號
};
 
class Teacher : virtual public Person
{
protected:
	int _id; // 職工編號
};
 
class Assistant : public Student, public Teacher
{
protected:
	string _majorCourse; // 主修課程
};
 
void Test()
{
	Assistant a;
	a._name = "peter";
}
 
int main()
{
	Test();
	return 0;
}

class A
{
public:
	int _a;
};
// class B : public A
class B : virtual public A
{
public:
	int _b;
};
// class C : public A
class C : virtual public A
{
public:
	int _c;
};
class D : public B, public C
{
public:
	int _d;
};
int main()
{
	D d;
	d.B::_a = 1;
	d.C::_a = 2;
	d._b = 3;
	d._c = 4;
	d._d = 5;
	return 0;
}