构造函数的使用

/*<span style="font-size:32px;color:#FF0000;">在写一个简单的多态例子的时候总是出错，后来发现是
在构造函数上面有问题  少写了new，结果依旧运行，那
么构造函数返回了什么呢</span>*/

#include "stdafx.h"
#include<iostream>
#include<string>
using namespace std;
class person {
protected:
	string name;
public:
	virtual void showinfo();
	person(string name) :name(name) { cout << "this is person 构造函数" << endl; }
	person(person& rhs) { cout << "this is person拷贝构造函数" << endl; }
};
void person::showinfo() {
	cout << name<<endl;
}
class teacher :public person{
protected:
	string prefession;
public:
	void showinfo();
	teacher(teacher& rhs):person(rhs) { cout << "this is teacher 拷贝构造函数" << endl; }
	teacher(string name, string prefession) :person(name), prefession(prefession) { cout << "this is teacher 构造函数" << endl; }
};
void teacher::showinfo() {
	cout << name << " " << prefession << endl;
}
class student :public person {
protected:
	int s_number;
public:
	void showinfo();
	student(string name, int nu) :person(name), s_number(nu) { cout << "this is student 构造函数"<<endl; }
};
void student::showinfo() {
	cout << name << " " << s_number << endl;
}
int main()
{
	person d = teacher("luyu", "jiaoshi");//构造函数这样写
	d.showinfo();
	person* b = new teacher("luyu", "jiaoshi");//或者这么写
	b->showinfo();
        delete b;
        return 0;
}

运行结果是这样的，多调用了一个拷贝构造函数，那么构造函数返回的应该是this指针

对汇编无感，知乎上面的朋友给力

版权意识要浓厚

构造函数返回了一个this指针。。。。